Implement support for C compilation

We now have two new modules: cc (c-common) and c.

52 files changed, 2912 insertions, 1359 deletions

diff --git a/build2/algorithm b/build2/algorithm
index d52cca9..651ef24 100644
--- a/build2/algorithm
+++ b/build2/algorithm
@@ -201,6 +201,15 @@ namespace build2
   T*
   execute_prerequisites (action, target&, const timestamp&);
 
+  target*
+  execute_prerequisites (const target_type&,
+                         action, target&, const timestamp&);
+
+  template <typename T>
+  T*
+  execute_prerequisites (const target_type&,
+                         action, target&, const timestamp&);
+
   // Return noop_recipe instead of using this function directly.
   //
   target_state
@@ -243,6 +252,5 @@ namespace build2
 }
 
 #include <build2/algorithm.ixx>
-#include <build2/algorithm.txx>
 
 #endif // BUILD2_ALGORITHM
diff --git a/build2/algorithm.cxx b/build2/algorithm.cxx
index a7126cc..cae6645 100644
--- a/build2/algorithm.cxx
+++ b/build2/algorithm.cxx
@@ -454,6 +454,54 @@ namespace build2
     return e;
   }
 
+  target*
+  execute_prerequisites (const target_type& tt,
+                         action a, target& t, const timestamp& mt)
+  {
+    bool e (mt == timestamp_nonexistent);
+    target* r (nullptr);
+
+    for (target* pt: t.prerequisite_targets)
+    {
+      if (pt == nullptr) // Skip ignored.
+        continue;
+
+      target_state ts (execute (a, *pt));
+
+      if (!e)
+      {
+        // If this is an mtime-based target, then compare timestamps.
+        //
+        if (auto mpt = dynamic_cast<const mtime_target*> (pt))
+        {
+          timestamp mp (mpt->mtime ());
+
+          // What do we do if timestamps are equal? This can happen, for
+          // example, on filesystems that don't have subsecond resolution.
+          // There is not much we can do here except detect the case where
+          // the prerequisite was changed in this run which means the
+          // action must be executed on the target as well.
+          //
+          if (mt < mp || (mt == mp && ts == target_state::changed))
+            e = true;
+        }
+        else
+        {
+          // Otherwise we assume the prerequisite is newer if it was changed.
+          //
+          if (ts == target_state::changed)
+            e = true;
+        }
+      }
+
+      if (pt->is_a (tt))
+        r = pt;
+    }
+
+    assert (r != nullptr);
+    return e ? r : nullptr;
+  }
+
   target_state
   noop_action (action a, target& t)
   {
diff --git a/build2/algorithm.ixx b/build2/algorithm.ixx
index 17c9d8d..c9c6b02 100644
--- a/build2/algorithm.ixx
+++ b/build2/algorithm.ixx
@@ -200,4 +200,19 @@ namespace build2
     default: return execute_impl (a, t);
     }
   }
+
+  template <typename T>
+  inline T*
+  execute_prerequisites (action a, target& t, const timestamp& mt)
+  {
+    return static_cast<T*> (execute_prerequisites (T::static_type, a, t, mt));
+  }
+
+  template <typename T>
+  inline T*
+  execute_prerequisites (const target_type& tt,
+                         action a, target& t, const timestamp& mt)
+  {
+    return static_cast<T*> (execute_prerequisites (tt, a, t, mt));
+  }
 }
diff --git a/build2/algorithm.txx b/build2/algorithm.txx
deleted file mode 100644
index 1431d32..0000000
--- a/build2/algorithm.txx
+++ /dev/null
@@ -1,58 +0,0 @@
-// file      : build2/algorithm.txx -*- C++ -*-
-// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-namespace build2
-{
-  template <typename T>
-  T*
-  execute_prerequisites (action a, target& t, const timestamp& mt)
-  {
-    //@@ Can factor the bulk of it into a non-template code. Can
-    // either do a function template that will do dynamic_cast check
-    // or can scan the target type info myself. I think latter.
-    //
-    bool e (mt == timestamp_nonexistent);
-    T* r (nullptr);
-
-    for (target* pt: t.prerequisite_targets)
-    {
-      if (pt == nullptr) // Skip ignored.
-        continue;
-
-      target_state ts (execute (a, *pt));
-
-      if (!e)
-      {
-        // If this is an mtime-based target, then compare timestamps.
-        //
-        if (auto mpt = dynamic_cast<const mtime_target*> (pt))
-        {
-          timestamp mp (mpt->mtime ());
-
-          // What do we do if timestamps are equal? This can happen, for
-          // example, on filesystems that don't have subsecond resolution.
-          // There is not much we can do here except detect the case where
-          // the prerequisite was changed in this run which means the
-          // action must be executed on the target as well.
-          //
-          if (mt < mp || (mt == mp && ts == target_state::changed))
-            e = true;
-        }
-        else
-        {
-          // Otherwise we assume the prerequisite is newer if it was changed.
-          //
-          if (ts == target_state::changed)
-            e = true;
-        }
-      }
-
-      if (T* tmp = dynamic_cast<T*> (pt))
-        r = tmp;
-    }
-
-    assert (r != nullptr);
-    return e ? r : nullptr;
-  }
-}
diff --git a/build2/b.cxx b/build2/b.cxx
index a14b998..5167cf6 100644
--- a/build2/b.cxx
+++ b/build2/b.cxx
@@ -41,6 +41,8 @@ using namespace std;
 #include <build2/config/module>
 #include <build2/dist/module>
 #include <build2/bin/module>
+#include <build2/c/init>
+#include <build2/cc/init>
 #include <build2/cxx/module>
 #include <build2/cli/module>
 #include <build2/test/module>
@@ -183,19 +185,37 @@ main (int argc, char* argv[])
 
     // Register builtin modules.
     //
-    builtin_modules["config"]  = module_functions {&config::boot,
-                                                   &config::init};
-    builtin_modules["dist"]    = module_functions {&dist::boot, &dist::init};
-    builtin_modules["test"]    = module_functions {&test::boot, &test::init};
-    builtin_modules["install"] = module_functions {&install::boot,
-                                                   &install::init};
-
-    builtin_modules["bin"] = module_functions {nullptr, &bin::init};
-    builtin_modules["bin.ar"] = module_functions {nullptr, &bin::ar_init};
-    builtin_modules["bin.ld"] = module_functions {nullptr, &bin::ld_init};
-    builtin_modules["bin.rc"] = module_functions {nullptr, &bin::rc_init};
-    builtin_modules["cxx"] = module_functions {nullptr, &cxx::init};
-    builtin_modules["cli"] = module_functions {nullptr, &cli::init};
+    {
+      using mf = module_functions;
+      auto& bm (builtin_modules);
+
+      bm["config"]  = mf {&config::boot, &config::init};
+      bm["dist"]    = mf {&dist::boot, &dist::init};
+      bm["test"]    = mf {&test::boot, &test::init};
+      bm["install"] = mf {&install::boot, &install::init};
+
+      bm["bin.config"] = mf {nullptr, &bin::config_init};
+      bm["bin"] = mf {nullptr, &bin::init};
+      bm["bin.ar.config"] = mf {nullptr, &bin::ar_config_init};
+      bm["bin.ar"] = mf {nullptr, &bin::ar_init};
+      bm["bin.ld.config"] = mf {nullptr, &bin::ld_config_init};
+      bm["bin.ld"] = mf {nullptr, &bin::ld_init};
+      bm["bin.rc.config"] = mf {nullptr, &bin::rc_config_init};
+      bm["bin.rc"] = mf {nullptr, &bin::rc_init};
+
+      bm["cc.vars"] = mf {nullptr, &cc::vars_init};
+      bm["cc.config"] = mf {nullptr, &cc::config_init};
+      bm["cc.core"] = mf {nullptr, &cc::core_init};
+      bm["cc"] = mf {nullptr, &cc::init};
+
+      bm["c.config"] = mf {nullptr, &c::config_init};
+      bm["c"] = mf {nullptr, &c::init};
+
+      bm["cxx.config"] = mf {nullptr, &cxx::config_init};
+      bm["cxx"] = mf {nullptr, &cxx::init};
+
+      bm["cli"] = mf {nullptr, &cli::init};
+    }
 
     // Figure out work and home directories.
     //
diff --git a/build2/bin/module b/build2/bin/module
index 8fb9274..8cf0255 100644
--- a/build2/bin/module
+++ b/build2/bin/module
@@ -15,6 +15,15 @@ namespace build2
   namespace bin
   {
     bool
+    config_init (scope&,
+                 scope&,
+                 const location&,
+                 unique_ptr<module_base>&,
+                 bool,
+                 bool,
+                 const variable_map&);
+
+    bool
     init (scope&,
           scope&,
           const location&,
@@ -24,6 +33,15 @@ namespace build2
           const variable_map&);
 
     bool
+    ar_config_init (scope&,
+                    scope&,
+                    const location&,
+                    unique_ptr<module_base>&,
+                    bool,
+                    bool,
+                    const variable_map&);
+
+    bool
     ar_init (scope&,
              scope&,
              const location&,
@@ -33,6 +51,15 @@ namespace build2
              const variable_map&);
 
     bool
+    ld_config_init (scope&,
+                    scope&,
+                    const location&,
+                    unique_ptr<module_base>&,
+                    bool,
+                    bool,
+                    const variable_map&);
+
+    bool
     ld_init (scope&,
              scope&,
              const location&,
@@ -42,6 +69,15 @@ namespace build2
              const variable_map&);
 
     bool
+    rc_config_init (scope&,
+                    scope&,
+                    const location&,
+                    unique_ptr<module_base>&,
+                    bool,
+                    bool,
+                    const variable_map&);
+
+    bool
     rc_init (scope&,
              scope&,
              const location&,
diff --git a/build2/bin/module.cxx b/build2/bin/module.cxx
index 281a2e4..6d9cda7 100644
--- a/build2/bin/module.cxx
+++ b/build2/bin/module.cxx
@@ -33,39 +33,19 @@ namespace build2
     static const strings liba_lib {"static"};
     static const strings libs_lib {"shared"};
 
-    // Apply the specified stem to the config.bin.pattern. If there is no
-    // pattern, then return the stem itself. Assume the pattern is valid,
-    // i.e., contains single '*'.
-    //
-    static string
-    apply (const lookup& pattern, const char* stem)
-    {
-      if (!pattern)
-        return stem;
-
-      const string& p (cast<string> (pattern));
-      size_t i (p.find ('*'));
-      assert (i != string::npos);
-
-      string r (p, 0, i++);
-      r.append (stem);
-      r.append (p, i, p.size () - i);
-      return r;
-    }
-
     bool
-    init (scope& r,
-          scope& b,
-          const location& loc,
-          unique_ptr<module_base>&,
-          bool first,
-          bool,
-          const variable_map& config_hints)
+    config_init (scope& r,
+                 scope& b,
+                 const location& loc,
+                 unique_ptr<module_base>&,
+                 bool first,
+                 bool,
+                 const variable_map& hints)
     {
-      tracer trace ("bin::init");
+      tracer trace ("bin::config_init");
       l5 ([&]{trace << "for " << b.out_path ();});
 
-      // Enter module variables.
+      // Enter configuration variables.
       //
       if (first)
       {
@@ -87,8 +67,6 @@ namespace build2
         v.insert<strings>   ("bin.liba.lib");
         v.insert<strings>   ("bin.libs.lib");
         v.insert<dir_paths> ("bin.rpath");
-
-        v.insert<string>    ("bin.libprefix",        true);
       }
 
       // Configure.
@@ -166,7 +144,7 @@ namespace build2
           bool hint (false);
           if (v == nullptr)
           {
-            if (auto l = config_hints[var])
+            if (auto l = hints[var])
             {
               v = l.value;
               hint = true;
@@ -241,7 +219,7 @@ namespace build2
           //
           if (v == nullptr)
           {
-            if (auto l = config_hints[var])
+            if (auto l = hints[var])
               v = l.value;
           }
 
@@ -276,6 +254,35 @@ namespace build2
         }
       }
 
+      return true;
+    }
+
+    bool
+    init (scope& r,
+          scope& b,
+          const location& loc,
+          unique_ptr<module_base>&,
+          bool first,
+          bool,
+          const variable_map& hints)
+    {
+      tracer trace ("bin::init");
+      l5 ([&]{trace << "for " << b.out_path ();});
+
+      // Enter the rest of the variables.
+      //
+      if (first)
+      {
+        auto& v (var_pool);
+
+        v.insert<string> ("bin.libprefix", true);
+      }
+
+      // Load bin.config.
+      //
+      if (!cast_false<bool> (b["bin.config.loaded"]))
+        load_module ("bin.config", r, b, loc, false, hints);
+
       // Cache some config values we will be needing below.
       //
       const string& tclass (cast<string> (r["bin.target.class"]));
@@ -363,24 +370,44 @@ namespace build2
       return true;
     }
 
+    // Apply the specified stem to the config.bin.pattern. If there is no
+    // pattern, then return the stem itself. Assume the pattern is valid,
+    // i.e., contains single '*'.
+    //
+    static string
+    apply (const lookup& pattern, const char* stem)
+    {
+      if (!pattern)
+        return stem;
+
+      const string& p (cast<string> (pattern));
+      size_t i (p.find ('*'));
+      assert (i != string::npos);
+
+      string r (p, 0, i++);
+      r.append (stem);
+      r.append (p, i, p.size () - i);
+      return r;
+    }
+
     bool
-    ar_init (scope& r,
-             scope& b,
-             const location& loc,
-             unique_ptr<module_base>&,
-             bool first,
-             bool,
-             const variable_map& config_hints)
+    ar_config_init (scope& r,
+                    scope& b,
+                    const location& loc,
+                    unique_ptr<module_base>&,
+                    bool first,
+                    bool,
+                    const variable_map& hints)
     {
-      tracer trace ("bin::ar_init");
+      tracer trace ("bin::ar_config_init");
       l5 ([&]{trace << "for " << b.out_path ();});
 
-      // Make sure the bin core is loaded.
+      // Make sure bin.config is loaded.
       //
-      if (!cast_false<bool> (b["bin.loaded"]))
-        load_module ("bin", r, b, loc, false, config_hints);
+      if (!cast_false<bool> (b["bin.config.loaded"]))
+        load_module ("bin.config", r, b, loc, false, hints);
 
-      // Enter module variables.
+      // Enter configuration variables.
       //
       if (first)
       {
@@ -480,23 +507,46 @@ namespace build2
     }
 
     bool
-    ld_init (scope& r,
+    ar_init (scope& r,
              scope& b,
              const location& loc,
              unique_ptr<module_base>&,
-             bool first,
              bool,
-             const variable_map& config_hints)
+             bool,
+             const variable_map& hints)
     {
-      tracer trace ("bin::ld_init");
+      tracer trace ("bin::ar_init");
       l5 ([&]{trace << "for " << b.out_path ();});
 
-      // Make sure the bin core is loaded.
+      // Make sure the bin core and ar.config are loaded.
       //
       if (!cast_false<bool> (b["bin.loaded"]))
-        load_module ("bin", r, b, loc, false, config_hints);
+        load_module ("bin", r, b, loc, false, hints);
+
+      if (!cast_false<bool> (b["bin.ar.config.loaded"]))
+        load_module ("bin.ar.config", r, b, loc, false, hints);
+
+      return true;
+    }
 
-      // Enter module variables.
+    bool
+    ld_config_init (scope& r,
+                    scope& b,
+                    const location& loc,
+                    unique_ptr<module_base>&,
+                    bool first,
+                    bool,
+                    const variable_map& hints)
+    {
+      tracer trace ("bin::ld_config_init");
+      l5 ([&]{trace << "for " << b.out_path ();});
+
+      // Make sure bin.config is loaded.
+      //
+      if (!cast_false<bool> (b["bin.config.loaded"]))
+        load_module ("bin.config", r, b, loc, false, hints);
+
+      // Enter configuration variables.
       //
       if (first)
       {
@@ -542,6 +592,29 @@ namespace build2
         r.assign<string> ("bin.ld.checksum") = move (ldi.checksum);
       }
 
+      return true;
+    }
+
+    bool
+    ld_init (scope& r,
+             scope& b,
+             const location& loc,
+             unique_ptr<module_base>&,
+             bool,
+             bool,
+             const variable_map& hints)
+    {
+      tracer trace ("bin::ld_init");
+      l5 ([&]{trace << "for " << b.out_path ();});
+
+      // Make sure the bin core and ld.config are loaded.
+      //
+      if (!cast_false<bool> (b["bin.loaded"]))
+        load_module ("bin", r, b, loc, false, hints);
+
+      if (!cast_false<bool> (b["bin.ld.config.loaded"]))
+        load_module ("bin.ld.config", r, b, loc, false, hints);
+
       const string& lid (cast<string> (r["bin.ld.id"]));
 
       // Register the pdb{} target if using the VC toolchain.
@@ -559,23 +632,23 @@ namespace build2
     }
 
     bool
-    rc_init (scope& r,
-             scope& b,
-             const location& loc,
-             unique_ptr<module_base>&,
-             bool first,
-             bool,
-             const variable_map& config_hints)
+    rc_config_init (scope& r,
+                    scope& b,
+                    const location& loc,
+                    unique_ptr<module_base>&,
+                    bool first,
+                    bool,
+                    const variable_map& hints)
     {
-      tracer trace ("bin::rc_init");
+      tracer trace ("bin::rc_config_init");
       l5 ([&]{trace << "for " << b.out_path ();});
 
-      // Make sure the bin core is loaded.
+      // Make sure bin.config is loaded.
       //
-      if (!cast_false<bool> (b["bin.loaded"]))
-        load_module ("bin", r, b, loc, false, config_hints);
+      if (!cast_false<bool> (b["bin.config.loaded"]))
+        load_module ("bin.config", r, b, loc, false, hints);
 
-      // Enter module variables.
+      // Enter configuration variables.
       //
       if (first)
       {
@@ -623,5 +696,28 @@ namespace build2
 
       return true;
     }
+
+    bool
+    rc_init (scope& r,
+             scope& b,
+             const location& loc,
+             unique_ptr<module_base>&,
+             bool,
+             bool,
+             const variable_map& hints)
+    {
+      tracer trace ("bin::rc_init");
+      l5 ([&]{trace << "for " << b.out_path ();});
+
+      // Make sure the bin core and rc.config are loaded.
+      //
+      if (!cast_false<bool> (b["bin.loaded"]))
+        load_module ("bin", r, b, loc, false, hints);
+
+      if (!cast_false<bool> (b["bin.rc.config.loaded"]))
+        load_module ("bin.rc.config", r, b, loc, false, hints);
+
+      return true;
+    }
   }
 }
diff --git a/build2/buildfile b/build2/buildfile
index 3986015..b0e9cf0 100644
--- a/build2/buildfile
+++ b/build2/buildfile
@@ -5,7 +5,7 @@
 import libs = libbutl%lib{butl}
 
 exe{b}:                                       \
-        {hxx ixx txx cxx}{ algorithm        } \
+        {hxx ixx     cxx}{ algorithm        } \
         {            cxx}{ b                } \
         {hxx ixx     cxx}{ b-options        } \
         {hxx     txx cxx}{ context          } \
@@ -38,23 +38,28 @@ exe{b}:                                       \
     bin/{hxx         cxx}{ module           } \
     bin/{hxx         cxx}{ rule             } \
     bin/{hxx         cxx}{ target           } \
+      c/{hxx         cxx}{ init             } \
+      c/{hxx            }{ target           } \
+     cc/{hxx            }{ common           } \
+     cc/{hxx         cxx}{ compile          } \
+     cc/{hxx         cxx}{ guess            } \
+     cc/{hxx         cxx}{ init             } \
+     cc/{hxx         cxx}{ install          } \
+     cc/{hxx         cxx}{ link             } \
+     cc/{hxx         cxx}{ module           } \
+     cc/{            cxx}{ msvc             } \
+     cc/{hxx         cxx}{ target           } \
+     cc/{hxx ixx     cxx}{ utility          } \
+     cc/{            cxx}{ windows-manifest } \
+     cc/{            cxx}{ windows-rpath    } \
     cli/{hxx         cxx}{ module           } \
     cli/{hxx         cxx}{ rule             } \
     cli/{hxx         cxx}{ target           } \
  config/{hxx         cxx}{ module           } \
  config/{hxx         cxx}{ operation        } \
  config/{hxx     txx cxx}{ utility          } \
-    cxx/{hxx         cxx}{ common           } \
-    cxx/{hxx         cxx}{ compile          } \
-    cxx/{hxx         cxx}{ guess            } \
-    cxx/{hxx         cxx}{ install          } \
-    cxx/{hxx         cxx}{ link             } \
     cxx/{hxx         cxx}{ module           } \
-    cxx/{            cxx}{ msvc             } \
     cxx/{hxx         cxx}{ target           } \
-    cxx/{hxx ixx     cxx}{ utility          } \
-    cxx/{            cxx}{ windows-manifest } \
-    cxx/{            cxx}{ windows-rpath    } \
    dist/{hxx         cxx}{ module           } \
    dist/{hxx         cxx}{ operation        } \
    dist/{hxx         cxx}{ rule             } \
diff --git a/build2/c/init b/build2/c/init
new file mode 100644
index 0000000..04f193e
--- /dev/null
+++ b/build2/c/init
@@ -0,0 +1,37 @@
+// file      : build2/c/init -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_C_INIT
+#define BUILD2_C_INIT
+
+#include <build2/types>
+#include <build2/utility>
+
+#include <build2/module>
+
+namespace build2
+{
+  namespace c
+  {
+    bool
+    config_init (scope&,
+                 scope&,
+                 const location&,
+                 unique_ptr<module_base>&,
+                 bool,
+                 bool,
+                 const variable_map&);
+
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
+  }
+}
+
+#endif // BUILD2_C_INIT
diff --git a/build2/c/init.cxx b/build2/c/init.cxx
new file mode 100644
index 0000000..7795181
--- /dev/null
+++ b/build2/c/init.cxx
@@ -0,0 +1,240 @@
+// file      : build2/c/init.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <build2/c/init>
+
+#include <build2/scope>
+#include <build2/context>
+#include <build2/diagnostics>
+
+#include <build2/cc/module>
+
+#include <build2/c/target>
+
+using namespace std;
+using namespace butl;
+
+namespace build2
+{
+  namespace c
+  {
+    using cc::config_module;
+
+    class module: public cc::module
+    {
+    public:
+      explicit
+      module (data&& d): common (move (d)), cc::module (move (d)) {}
+
+      bool
+      translate_std (string&, scope&, const value&) const override;
+    };
+
+    bool module::
+    translate_std (string& s, scope& r, const value& val) const
+    {
+      const string& v (cast<string> (val));
+
+      if (cid == "msvc")
+      {
+        // Standard-wise, with VC you get what you get. The question is
+        // whether we should verify that the requested standard is provided by
+        // this VC version. And if so, from which version should we say VC
+        // supports 90, 99, and 11? We should probably be as loose as possible
+        // here since the author will always be able to tighten (but not
+        // loosen) this in the buildfile (i.e., detect unsupported versions).
+        //
+        // The state of affairs seem to be (from Herb Sutter's blog):
+        //
+        // 10.0 - most of C95 plus a few C99 features
+        // 11.0 - partial support for the C++11 subset of C11
+        // 12.0 - more C11 features from the C++11 subset, most of C99
+        //
+        // So let's say C99 is supported from 10.0 and C11 from 11.0. And C90
+        // is supported by everything we care to support.
+        //
+        if (v != "90")
+        {
+          uint64_t cver (cast<uint64_t> (r[x_version_major]));
+
+          if ((v == "99" && cver < 16) || // Since VS2010/10.0.
+              (v == "11" && cver < 17))   // Since VS2012/11.0.
+          {
+            fail << "C" << v << " is not supported by "
+                 << cast<string> (r[x_signature]) <<
+              info << "required by " << project (r) << '@' << r.out_path ();
+          }
+        }
+
+        return false;
+      }
+      else
+      {
+        // 90 and 89 are the same standard. Translate 99 to 9x and 11 to 1x
+        // for compatibility with older versions of the compilers.
+        //
+        s = "-std=";
+
+        if (v == "90")
+          s += "c90";
+        else if (v == "99")
+          s += "c9x";
+        else if (v == "11")
+          s += "c1x";
+        else
+          s += v; // In case the user specifies something like 'gnu11'.
+
+        return true;
+      }
+    }
+
+    bool
+    config_init (scope& r,
+                 scope& b,
+                 const location& loc,
+                 unique_ptr<module_base>& m,
+                 bool first,
+                 bool,
+                 const variable_map& hints)
+    {
+      tracer trace ("c::config_init");
+      l5 ([&]{trace << "for " << b.out_path ();});
+
+      if (first)
+      {
+        // Load cc.vars so that we can cache all the cc.* variables.
+        //
+        if (!cast_false<bool> (b["cc.vars.loaded"]))
+          load_module ("cc.vars", r, b, loc);
+
+        // Enter all the variables and initialize the module data.
+        //
+        auto& v (var_pool);
+
+        cc::config_data d {
+          cc::lang::c,
+
+          "c",
+          "c",
+          "gcc",
+
+          // Note: some overridable, some not.
+          //
+          v.insert<path>     ("config.c",          true),
+          v.insert<strings>  ("config.c.poptions", true),
+          v.insert<strings>  ("config.c.coptions", true),
+          v.insert<strings>  ("config.c.loptions", true),
+          v.insert<strings>  ("config.c.libs",     true),
+
+          v.insert<strings>  ("c.poptions"),
+          v.insert<strings>  ("c.coptions"),
+          v.insert<strings>  ("c.loptions"),
+          v.insert<strings>  ("c.libs"),
+
+          v["cc.poptions"],
+          v["cc.coptions"],
+          v["cc.loptions"],
+          v["cc.libs"],
+
+          v.insert<strings>  ("c.export.poptions"),
+          v.insert<strings>  ("c.export.coptions"),
+          v.insert<strings>  ("c.export.loptions"),
+          v.insert<strings>  ("c.export.libs"),
+
+          v["cc.export.poptions"],
+          v["cc.export.coptions"],
+          v["cc.export.loptions"],
+          v["cc.export.libs"],
+
+          v.insert<string>   ("c.std", true),
+
+          v.insert<string>   ("c.id"),
+          v.insert<string>   ("c.id.type"),
+          v.insert<string>   ("c.id.variant"),
+
+          v.insert<string>   ("c.version"),
+          v.insert<uint64_t> ("c.version.major"),
+          v.insert<uint64_t> ("c.version.minor"),
+          v.insert<uint64_t> ("c.version.patch"),
+          v.insert<string>   ("c.version.build"),
+
+          v.insert<string>   ("c.signature"),
+          v.insert<string>   ("c.checksum"),
+
+          v.insert<string>   ("c.target"),
+          v.insert<string>   ("c.target.cpu"),
+          v.insert<string>   ("c.target.vendor"),
+          v.insert<string>   ("c.target.system"),
+          v.insert<string>   ("c.target.version"),
+          v.insert<string>   ("c.target.class")
+        };
+
+        assert (m == nullptr);
+        m.reset (new config_module (move (d)));
+      }
+
+      static_cast<config_module&> (*m).init (r, b, loc, first, hints);
+      return true;
+    }
+
+    static const target_type* hdr[] =
+    {
+      &h::static_type,
+      nullptr
+    };
+
+    static const target_type* inc[] =
+    {
+      &h::static_type,
+      &c::static_type,
+      nullptr
+    };
+
+    bool
+    init (scope& r,
+          scope& b,
+          const location& loc,
+          unique_ptr<module_base>& m,
+          bool first,
+          bool,
+          const variable_map& hints)
+    {
+      tracer trace ("c::init");
+      l5 ([&]{trace << "for " << b.out_path ();});
+
+      // Load c.config.
+      //
+      if (!cast_false<bool> (b["c.config.loaded"]))
+        load_module ("c.config", r, b, loc, false, hints);
+
+      if (first)
+      {
+        config_module& cm (*r.modules.lookup<config_module> ("c.config"));
+
+        cc::data d {
+          cm,
+
+          "c.compile",
+          "c.link",
+          "c.install",
+
+          cast<string> (r[cm.x_id]),
+          cast<string> (r[cm.x_target]),
+          cast<string> (r[cm.x_target_system]),
+          cast<string> (r[cm.x_target_class]),
+
+          c::static_type,
+          hdr,
+          inc
+        };
+
+        assert (m == nullptr);
+        m.reset (new module (move (d)));
+      }
+
+      static_cast<module&> (*m).init (r, b, loc, first, hints);
+      return true;
+    }
+  }
+}
diff --git a/build2/c/target b/build2/c/target
new file mode 100644
index 0000000..bf40306
--- /dev/null
+++ b/build2/c/target
@@ -0,0 +1,22 @@
+// file      : build2/c/target -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_C_TARGET
+#define BUILD2_C_TARGET
+
+#include <build2/types>
+#include <build2/utility>
+
+#include <build2/cc/target>
+
+namespace build2
+{
+  namespace c
+  {
+    using cc::h;
+    using cc::c;
+  }
+}
+
+#endif // BUILD2_C_TARGET
diff --git a/build2/cc/common b/build2/cc/common
new file mode 100644
index 0000000..95f205a
--- /dev/null
+++ b/build2/cc/common
@@ -0,0 +1,172 @@
+// file      : build2/cc/common -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_CC_COMMON
+#define BUILD2_CC_COMMON
+
+#include <build2/types>
+#include <build2/utility>
+
+#include <build2/variable>
+
+#include <build2/cc/types>
+
+namespace build2
+{
+  namespace cc
+  {
+    // Data entries that define a concrete c-family module (e.g., c or cxx).
+    // These classes are used as a virtual bases by the rules as well as the
+    // modules. This way the member variables can be referenced as is, without
+    // any extra decorations (in other words, it is a bunch of data members
+    // that can be shared between several classes/instances).
+    //
+    struct config_data
+    {
+      lang x_lang;
+
+      const char* x;         // Module name ("c", "cxx").
+      const char* x_name;    // Compiler name ("c", "c++").
+      const char* x_default; // Compiler default ("gcc", "g++").
+
+      const variable& config_x;
+      const variable& config_x_poptions;
+      const variable& config_x_coptions;
+      const variable& config_x_loptions;
+      const variable& config_x_libs;
+
+      const variable& x_poptions;
+      const variable& x_coptions;
+      const variable& x_loptions;
+      const variable& x_libs;
+
+      const variable& c_poptions; // cc.*
+      const variable& c_coptions;
+      const variable& c_loptions;
+      const variable& c_libs;
+
+      const variable& x_export_poptions;
+      const variable& x_export_coptions;
+      const variable& x_export_loptions;
+      const variable& x_export_libs;
+
+      const variable& c_export_poptions; // cc.export.*
+      const variable& c_export_coptions;
+      const variable& c_export_loptions;
+      const variable& c_export_libs;
+
+      const variable& x_std;
+
+      const variable& x_id;
+      const variable& x_id_type;
+      const variable& x_id_variant;
+
+      const variable& x_version;
+      const variable& x_version_major;
+      const variable& x_version_minor;
+      const variable& x_version_patch;
+      const variable& x_version_build;
+
+      const variable& x_signature;
+      const variable& x_checksum;
+
+      const variable& x_target;
+      const variable& x_target_cpu;
+      const variable& x_target_vendor;
+      const variable& x_target_system;
+      const variable& x_target_version;
+      const variable& x_target_class;
+    };
+
+    struct data: config_data
+    {
+      const char* x_compile; // Rule names.
+      const char* x_link;
+      const char* x_install;
+
+      // Cached values for some commonly-used variables.
+      //
+      const string& cid;     // x.id
+      const string& ctg;     // x.target
+      const string& tsys;    // x.target.system
+      const string& tclass;  // x.target.class
+
+      const target_type& x_src;  // Source target type (c{}, cxx{}).
+
+      // Array of target types that are considered headers. Keep them in the
+      // most likely to appear order and terminate with NULL.
+      //
+      const target_type* const* x_hdr;
+
+      template <typename T>
+      bool
+      x_header (const T& t) const
+      {
+        for (const target_type* const* ht (x_hdr); *ht != nullptr; ++ht)
+          if (t.is_a (**ht))
+            return true;
+
+        return false;
+      }
+
+      // Array of target types that can be #include'd. Used to reverse-lookup
+      // extensions to target types. Keep them in the most likely to appear
+      // order and terminate with NULL.
+      //
+      const target_type* const* x_inc;
+
+      // Aggregate-like constructor with from-base support.
+      //
+      data (const config_data& cd,
+            const char* compile,
+            const char* link,
+            const char* install,
+            const string& id,
+            const string& tg,
+            const string& sys,
+            const string& class_,
+            const target_type& src,
+            const target_type* const* hdr,
+            const target_type* const* inc)
+          : config_data (cd),
+            x_compile (compile), x_link (link), x_install (install),
+            cid (id), ctg (tg), tsys (sys), tclass (class_),
+            x_src (src), x_hdr (hdr), x_inc (inc) {}
+    };
+
+    class common: protected data
+    {
+    public:
+      common (data&& d): data (move (d)) {}
+
+      // Language standard (x.std) mapping. T is either target or scope.
+      //
+      template <typename T>
+      void
+      append_std (cstrings& args, scope& root, T& t, string& storage) const
+      {
+        if (auto l = t[x_std])
+          if (translate_std (storage, root, *l))
+            args.push_back (storage.c_str ());
+      }
+
+      template <typename T>
+      void
+      hash_std (sha256& csum, scope& root, T& t) const
+      {
+        string s;
+        if (auto l = t[x_std])
+          if (translate_std (s, root, *l))
+            csum.append (s);
+      }
+
+      // Return true if there is an option (stored in the first argument).
+      //
+      virtual bool
+      translate_std (string&, scope&, const value&) const = 0;
+    };
+  }
+}
+
+#endif // BUILD2_CC_COMMON
diff --git a/build2/cc/compile b/build2/cc/compile
new file mode 100644
index 0000000..6e20836
--- /dev/null
+++ b/build2/cc/compile
@@ -0,0 +1,82 @@
+// file      : build2/cc/compile -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_CC_COMPILE
+#define BUILD2_CC_COMPILE
+
+#include <butl/path-map>
+
+#include <build2/types>
+#include <build2/utility>
+
+#include <build2/rule>
+
+#include <build2/cc/types>
+#include <build2/cc/common>
+
+namespace build2
+{
+  class depdb;
+
+  namespace cc
+  {
+    class link;
+
+    class compile: public rule, virtual common
+    {
+    public:
+      compile (data&&, const link&);
+
+      virtual match_result
+      match (action, target&, const string& hint) const;
+
+      virtual recipe
+      apply (action, target&, const match_result&) const;
+
+      target_state
+      perform_update (action, target&) const;
+
+      target_state
+      perform_clean (action, target&) const;
+
+    private:
+      // Mapping of include prefixes (e.g., foo in <foo/bar>) for auto-
+      // generated headers to directories where they will be generated.
+      //
+      // We are using a prefix map of directories (dir_path_map) instead
+      // of just a map in order also cover sub-paths (e.g., <foo/more/bar>
+      // if we continue with the example). Specifically, we need to make
+      // sure we don't treat foobar as a sub-directory of foo.
+      //
+      // @@ The keys should be normalized.
+      //
+      using prefix_map = butl::dir_path_map<dir_path>;
+
+      void
+      append_prefixes (prefix_map&, target&, const variable&) const;
+
+      void
+      append_lib_prefixes (prefix_map&, target&, lorder) const;
+
+      prefix_map
+      build_prefix_map (target&, lorder) const;
+
+      // Reverse-lookup target type from extension.
+      //
+      const target_type*
+      map_extension (scope&, const string&, const string&) const;
+
+      // Header dependency injection.
+      //
+      void
+      inject (action, target&, lorder, file&, scope&, depdb&) const;
+
+    private:
+      const link& link_;
+      const string rule_id;
+    };
+  }
+}
+
+#endif // BUILD2_CC_COMPILE
diff --git a/build2/cxx/compile.cxx b/build2/cc/compile.cxx
index 56c518b..b5bcc50 100644
--- a/build2/cxx/compile.cxx
+++ b/build2/cc/compile.cxx
@@ -1,16 +1,12 @@
-// file      : build2/cxx/compile.cxx -*- C++ -*-
+// file      : build2/cc/compile.cxx -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#include <build2/cxx/compile>
+#include <build2/cc/compile>
 
-#include <map>
-#include <limits>   // numeric_limits
 #include <cstdlib>  // exit()
 #include <iostream> // cerr
 
-#include <butl/path-map>
-
 #include <build2/depdb>
 #include <build2/scope>
 #include <build2/context>
@@ -19,26 +15,32 @@
 #include <build2/diagnostics>
 
 #include <build2/bin/target>
-#include <build2/cxx/target>
-
-#include <build2/cxx/link>
-#include <build2/cxx/common>
-#include <build2/cxx/utility>
 
+#include <build2/cc/link>    // search_library()
+#include <build2/cc/target>  // h
+#include <build2/cc/utility>
 
 using namespace std;
 using namespace butl;
 
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
     using namespace bin;
 
+    compile::
+    compile (data&& d, const link& l)
+        : common (move (d)),
+          link_ (l),
+          rule_id (string (x) += ".compile 1")
+    {
+    }
+
     match_result compile::
     match (action a, target& t, const string&) const
     {
-      tracer trace ("cxx::compile::match");
+      tracer trace (x, "compile::match");
 
       // @@ TODO:
       //
@@ -46,37 +48,29 @@ namespace build2
       // - if path already assigned, verify extension?
       //
 
-      // See if we have a C++ source file. Iterate in reverse so that
-      // a source file specified for an obj*{} member overrides the one
-      // specified for the group. Also "see through" groups.
+      // See if we have a source file. Iterate in reverse so that a source
+      // file specified for an obj*{} member overrides the one specified for
+      // the group. Also "see through" groups.
       //
       for (prerequisite_member p: reverse_group_prerequisite_members (a, t))
       {
-        if (p.is_a<cxx> ())
+        if (p.is_a (x_src))
           return p;
       }
 
-      l4 ([&]{trace << "no c++ source file for target " << t;});
+      l4 ([&]{trace << "no " << x_lang << " source file for target " << t;});
       return nullptr;
     }
 
-    static void
-    inject_prerequisites (action, target&, lorder, cxx&, scope&, depdb&);
-
     recipe compile::
     apply (action a, target& xt, const match_result& mr) const
     {
-      tracer trace ("cxx::compile");
+      tracer trace (x, "compile::apply");
 
       file& t (static_cast<file&> (xt));
 
       scope& bs (t.base_scope ());
       scope& rs (*bs.root_scope ());
-
-      const string& cid (cast<string> (rs["cxx.id"]));
-      const string& tsys (cast<string> (rs["cxx.target.system"]));
-      const string& tclass (cast<string> (rs["cxx.target.class"]));
-
       otype ct (compile_type (t));
 
       // Derive file name from target name.
@@ -129,22 +123,21 @@ namespace build2
       //
       fsdir* dir (inject_fsdir (a, t));
 
-      // Search and match all the existing prerequisites. The injection
-      // code (below) takes care of the ones it is adding.
+      // Search and match all the existing prerequisites. The injection code
+      // takes care of the ones it is adding.
       //
-      // When cleaning, ignore prerequisites that are not in the same
-      // or a subdirectory of our project root.
+      // When cleaning, ignore prerequisites that are not in the same or a
+      // subdirectory of our project root.
       //
       optional<dir_paths> lib_paths; // Extract lazily.
 
       for (prerequisite_member p: group_prerequisite_members (a, t))
       {
         // A dependency on a library is there so that we can get its
-        // cxx.export.poptions. In particular, making sure it is
-        // executed before us will only restrict parallelism. But we
-        // do need to pre-match it in order to get its
-        // prerequisite_targets populated. This is the "library
-        // meta-information protocol". See also append_lib_options()
+        // *.export.poptions. In particular, making sure it is executed before
+        // us will only restrict parallelism. But we do need to pre-match it
+        // in order to get its prerequisite_targets populated. This is the
+        // "library meta-information protocol". See also append_lib_options()
         // above.
         //
         if (p.is_a<lib> () || p.is_a<liba> () || p.is_a<libs> ())
@@ -156,7 +149,7 @@ namespace build2
             // any, they would be set by search_library()).
             //
             if (p.proj () == nullptr ||
-                link::search_library (lib_paths, p.prerequisite) == nullptr)
+                link_.search_library (lib_paths, p.prerequisite) == nullptr)
             {
               match_only (a, p.search ());
             }
@@ -184,11 +177,7 @@ namespace build2
         // t.prerequisite_targets since we used standard search() and match()
         // above.
         //
-        // @@ Ugly.
-        //
-        cxx& st (
-          dynamic_cast<cxx&> (
-            mr.target != nullptr ? *mr.target : *mr.prerequisite->target));
+        file& src (mr.as_target<file> ());
 
         // Make sure the output directory exists.
         //
@@ -208,14 +197,14 @@ namespace build2
 
         // First should come the rule name/version.
         //
-        if (dd.expect ("cxx.compile 1") != nullptr)
+        if (dd.expect (rule_id) != nullptr)
           l4 ([&]{trace << "rule mismatch forcing update of " << t;});
 
         // Then the compiler checksum. Note that here we assume it
         // incorporates the (default) target so that if the compiler changes
         // but only in what it targets, then the checksum will still change.
         //
-        if (dd.expect (cast<string> (rs["cxx.checksum"])) != nullptr)
+        if (dd.expect (cast<string> (rs[x_checksum])) != nullptr)
           l4 ([&]{trace << "compiler mismatch forcing update of " << t;});
 
         // Then the options checksum.
@@ -225,7 +214,7 @@ namespace build2
         //
         sha256 cs;
 
-        // Hash cxx.export.poptions from prerequisite libraries.
+        // Hash *.export.poptions from prerequisite libraries.
         //
         lorder lo (link_order (bs, ct));
         for (prerequisite& p: group_prerequisites (t))
@@ -236,12 +225,16 @@ namespace build2
             pt = &link_member (*l, lo);
 
           if (pt->is_a<liba> () || pt->is_a<libs> ())
-            hash_lib_options (cs, *pt, "cxx.export.poptions", lo);
+            hash_lib_options (cs, *pt, lo,
+                              c_export_poptions,
+                              x_export_poptions);
         }
 
-        hash_options (cs, t, "cxx.poptions");
-        hash_options (cs, t, "cxx.coptions");
-        hash_std (cs, rs, cid, t);
+        hash_options (cs, t, c_poptions);
+        hash_options (cs, t, x_poptions);
+        hash_options (cs, t, c_coptions);
+        hash_options (cs, t, x_coptions);
+        hash_std (cs, rs, t);
 
         if (ct == otype::s)
         {
@@ -256,7 +249,7 @@ namespace build2
 
         // Finally the source file.
         //
-        if (dd.expect (st.path ()) != nullptr)
+        if (dd.expect (src.path ()) != nullptr)
           l4 ([&]{trace << "source file mismatch forcing update of " << t;});
 
         // If any of the above checks resulted in a mismatch (different
@@ -266,65 +259,51 @@ namespace build2
         if (dd.writing () || dd.mtime () > t.mtime ())
           t.mtime (timestamp_nonexistent);
 
-        inject_prerequisites (a, t, lo, st, mr.prerequisite->scope, dd);
+        inject (a, t, lo, src, mr.prerequisite->scope, dd);
 
         dd.close ();
       }
 
       switch (a)
       {
-      case perform_update_id: return &perform_update;
-      case perform_clean_id: return &perform_clean;
-      default: return noop_recipe; // Configure update.
+      case perform_update_id:
+        return [this] (action a, target& t) {return perform_update (a, t);};
+      case perform_clean_id:
+        return [this] (action a, target& t) {return perform_clean (a, t);};
+      default:
+        return noop_recipe; // Configure update.
       }
     }
 
     // Reverse-lookup target type from extension.
     //
-    static const target_type*
-    map_extension (scope& s, const string& n, const string& e)
+    const target_type* compile::
+    map_extension (scope& s, const string& n, const string& e) const
     {
-      // We will just have to try all of the possible ones, in the
-      // "most likely to match" order.
+      // We will just have to try all of the possible ones, in the "most
+      // likely to match" order.
       //
-      const variable& var (var_pool.find ("extension"));
+      const variable& var (var_pool["extension"]);
 
-      auto test = [&s, &n, &e, &var] (const target_type& tt)
-        -> const target_type*
+      auto test = [&s, &n, &e, &var] (const target_type& tt) -> bool
       {
         if (auto l = s.find (var, tt, n))
           if (cast<string> (l) == e)
-            return &tt;
+            return true;
 
-        return nullptr;
+        return false;
       };
 
-      if (auto r = test (hxx::static_type)) return r;
-      if (auto r = test (h::static_type))   return r;
-      if (auto r = test (ixx::static_type)) return r;
-      if (auto r = test (txx::static_type)) return r;
-      if (auto r = test (cxx::static_type)) return r;
-      if (auto r = test (c::static_type))   return r;
+      for (const target_type* const* p (x_inc); *p != nullptr; ++p)
+        if (test (**p)) return *p;
 
       return nullptr;
     }
 
-    // Mapping of include prefixes (e.g., foo in <foo/bar>) for auto-
-    // generated headers to directories where they will be generated.
-    //
-    // We are using a prefix map of directories (dir_path_map) instead
-    // of just a map in order also cover sub-paths (e.g., <foo/more/bar>
-    // if we continue with the example). Specifically, we need to make
-    // sure we don't treat foobar as a sub-directory of foo.
-    //
-    // @@ The keys should be canonicalized.
-    //
-    using prefix_map = dir_path_map<dir_path>;
-
-    static void
-    append_prefixes (prefix_map& m, target& t, const char* var)
+    void compile::
+    append_prefixes (prefix_map& m, target& t, const variable& var) const
     {
-      tracer trace ("cxx::append_prefixes");
+      tracer trace (x, "append_prefixes");
 
       // If this target does not belong to any project (e.g, an
       // "imported as installed" library), then it can't possibly
@@ -411,11 +390,11 @@ namespace build2
       }
     }
 
-    // Append library prefixes based on the cxx.export.poptions variables
+    // Append library prefixes based on the *.export.poptions variables
     // recursively, prerequisite libraries first.
     //
-    static void
-    append_lib_prefixes (prefix_map& m, target& l, lorder lo)
+    void compile::
+    append_lib_prefixes (prefix_map& m, target& l, lorder lo) const
     {
       for (target* t: l.prerequisite_targets)
       {
@@ -429,17 +408,17 @@ namespace build2
           append_lib_prefixes (m, *t, lo);
       }
 
-      append_prefixes (m, l, "cxx.export.poptions");
+      append_prefixes (m, l, c_export_poptions);
+      append_prefixes (m, l, x_export_poptions);
     }
 
-    static prefix_map
-    build_prefix_map (target& t, lorder lo)
+    auto compile::
+    build_prefix_map (target& t, lorder lo) const -> prefix_map
     {
       prefix_map m;
 
-      // First process the include directories from prerequisite
-      // libraries. Note that here we don't need to see group
-      // members (see apply()).
+      // First process the include directories from prerequisite libraries.
+      // Note that here we don't need to see group members (see apply()).
       //
       for (prerequisite& p: group_prerequisites (t))
       {
@@ -454,7 +433,8 @@ namespace build2
 
       // Then process our own.
       //
-      append_prefixes (m, t, "cxx.poptions");
+      append_prefixes (m, t, c_poptions);
+      append_prefixes (m, t, x_poptions);
 
       return m;
     }
@@ -521,11 +501,10 @@ namespace build2
       return r;
     }
 
-    // Extract the include path from the VC++ /showIncludes output line.
-    // Return empty string if the line is not an include note or include
-    // error. Set the good_error flag if it is an include error (which means
-    // the process will terminate with the error status that needs to be
-    // ignored).
+    // Extract the include path from the VC /showIncludes output line. Return
+    // empty string if the line is not an include note or include error. Set
+    // the good_error flag if it is an include error (which means the process
+    // will terminate with the error status that needs to be ignored).
     //
     static string
     next_show (const string& l, bool& good_error)
@@ -534,7 +513,7 @@ namespace build2
       //
       assert (!good_error);
 
-      // VC++ /showIncludes output. The first line is the file being
+      // VC /showIncludes output. The first line is the file being
       // compiled. Then we have the list of headers, one per line, in this
       // form (text can presumably be translated):
       //
@@ -634,11 +613,15 @@ namespace build2
       }
     }
 
-    static void
-    inject_prerequisites (action a, target& t, lorder lo,
-                          cxx& s, scope& ds, depdb& dd)
+    void compile::
+    inject (action a,
+            target& t,
+            lorder lo,
+            file& src,
+            scope& ds,
+            depdb& dd) const
     {
-      tracer trace ("cxx::compile::inject_prerequisites");
+      tracer trace (x, "compile::inject");
 
       l6 ([&]{trace << "target: " << t;});
 
@@ -647,28 +630,24 @@ namespace build2
       //
       auto g (
         make_exception_guard (
-          [&s]()
+          [&src]()
           {
-            info << "while extracting header dependencies from " << s;
+            info << "while extracting header dependencies from " << src;
           }));
 
       scope& rs (t.root_scope ());
-      const string& cid (cast<string> (rs["cxx.id"]));
 
       // Initialize lazily, only if required.
       //
       cstrings args;
-      string cxx_std; // Storage.
+      string std; // Storage.
 
-      auto init_args = [&t, lo, &s, &rs, &cid, &args, &cxx_std] ()
+      auto init_args = [&t, lo, &src, &rs, &args, &std, this] ()
       {
-        const path& cxx (cast<path> (rs["config.cxx"]));
-        const string& tclass (cast<string> (rs["cxx.target.class"]));
+        args.push_back (cast<path> (rs[config_x]).string ().c_str ());
 
-        args.push_back (cxx.string ().c_str ());
-
-        // Add cxx.export.poptions from prerequisite libraries. Note
-        // that here we don't need to see group members (see apply()).
+        // Add *.export.poptions from prerequisite libraries. Note that here
+        // we don't need to see group members (see apply()).
         //
         for (prerequisite& p: group_prerequisites (t))
         {
@@ -678,15 +657,20 @@ namespace build2
             pt = &link_member (*l, lo);
 
           if (pt->is_a<liba> () || pt->is_a<libs> ())
-            append_lib_options (args, *pt, "cxx.export.poptions", lo);
+            append_lib_options (args, *pt, lo,
+                                c_export_poptions,
+                                x_export_poptions);
         }
 
-        append_options (args, t, "cxx.poptions");
+        append_options (args, t, c_poptions);
+        append_options (args, t, x_poptions);
 
-        // Some C++ options (e.g., -std, -m) affect the preprocessor.
+        // Some compile options (e.g., -std, -m) affect the preprocessor.
         //
-        append_options (args, t, "cxx.coptions");
-        append_std (args, rs, cid, t, cxx_std);
+        append_options (args, t, c_coptions);
+        append_options (args, t, x_coptions);
+
+        append_std (args, rs, t, std);
 
         if (t.is_a<objs> ())
         {
@@ -703,15 +687,15 @@ namespace build2
           // See perform_update() for details on overriding the default
           // exceptions and runtime.
           //
-          if (!find_option_prefix ("/EH", args))
+          if (x_lang == lang::cxx && !find_option_prefix ("/EH", args))
             args.push_back ("/EHsc");
 
           if (!find_option_prefixes ({"/MD", "/MT"}, args))
             args.push_back ("/MD");
 
           args.push_back ("/EP");           // Preprocess to stdout.
-          args.push_back ("/TP");           // Preprocess as C++.
           args.push_back ("/showIncludes"); // Goes to sterr becasue of /EP.
+          args.push_back (x_lang == lang::c ? "/TC" : "/TP"); // Compile as.
         }
         else
         {
@@ -734,7 +718,7 @@ namespace build2
         // @@ We will also have to use absolute -I paths to guarantee
         // that. Or just detect relative paths and error out?
         //
-        args.push_back (s.path ().string ().c_str ());
+        args.push_back (src.path ().string ().c_str ());
         args.push_back (nullptr);
       };
 
@@ -826,7 +810,7 @@ namespace build2
       // from the depdb cache or from the compiler run. Return whether the
       // extraction process should be restarted.
       //
-      auto add = [&trace, &update, &pm, a, &t, lo, &ds, &dd]
+      auto add = [&trace, &update, &pm, a, &t, lo, &ds, &dd, this]
         (path f, bool cache) -> bool
       {
         if (!f.absolute ())
@@ -926,8 +910,8 @@ namespace build2
             out = out_src (d, *rs);
         }
 
-        // If it is outside any project, or the project doesn't have
-        // such an extension, assume it is a plain old C header.
+        // If it is outside any project, or the project doesn't have such an
+        // extension, assume it is a plain old C header.
         //
         if (tt == nullptr)
           tt = &h::static_type;
@@ -980,7 +964,7 @@ namespace build2
       // But, before we do all that, make sure the source file itself if up to
       // date.
       //
-      if (update (s, dd.mtime ()))
+      if (update (src, dd.mtime ()))
       {
         // If the file got updated or is newer than the database, then we
         // cannot rely on the cache any further. However, the cached data
@@ -1099,7 +1083,7 @@ namespace build2
                     // this case the first line (and everything after it) is
                     // presumably diagnostics.
                     //
-                    if (l != s.path ().leaf ().string ())
+                    if (l != src.path ().leaf ().string ())
                     {
                       text << l;
                       bad_error = true;
@@ -1205,8 +1189,8 @@ namespace build2
                 }
               }
 
-              // In case of VC++, we are parsing stderr and if things go
-              // south, we need to copy the diagnostics for the user to see.
+              // In case of VC, we are parsing stderr and if things go south,
+              // we need to copy the diagnostics for the user to see.
               //
               // Note that the eof check is important: if the stream is at
               // eof, this and all subsequent writes to cerr will fail (and
@@ -1227,12 +1211,14 @@ namespace build2
                   throw failed ();
               }
               else if (bad_error)
-                fail << "expected error exist status from C++ compiler";
+                fail << "expected error exist status from " << x_lang
+                     << " compiler";
             }
             catch (const ifdstream::failure&)
             {
               pr.wait ();
-              fail << "unable to read C++ compiler header dependency output";
+              fail << "unable to read " << x_lang << " compiler header "
+                   << "dependency output";
             }
           }
           catch (const process_error& e)
@@ -1258,24 +1244,19 @@ namespace build2
     msvc_filter_cl (ifdstream&, const path& src);
 
     target_state compile::
-    perform_update (action a, target& xt)
+    perform_update (action a, target& xt) const
     {
       file& t (static_cast<file&> (xt));
-      cxx* s (execute_prerequisites<cxx> (a, t, t.mtime ()));
+      file* s (execute_prerequisites<file> (x_src, a, t, t.mtime ()));
 
       if (s == nullptr)
         return target_state::unchanged;
 
       scope& bs (t.base_scope ());
       scope& rs (*bs.root_scope ());
-
-      const path& cxx (cast<path> (rs["config.cxx"]));
-      const string& cid (cast<string> (rs["cxx.id"]));
-      const string& tclass (cast<string> (rs["cxx.target.class"]));
-
       otype ct (compile_type (t));
 
-      cstrings args {cxx.string ().c_str ()};
+      cstrings args {cast<path> (rs[config_x]).string ().c_str ()};
 
       // Translate paths to relative (to working directory) ones. This
       // results in easier to read diagnostics.
@@ -1283,8 +1264,8 @@ namespace build2
       path relo (relative (t.path ()));
       path rels (relative (s->path ()));
 
-      // Add cxx.export.poptions from prerequisite libraries. Note that
-      // here we don't need to see group members (see apply()).
+      // Add *.export.poptions from prerequisite libraries. Note that here we
+      // don't need to see group members (see apply()).
       //
       lorder lo (link_order (bs, ct));
       for (prerequisite& p: group_prerequisites (t))
@@ -1295,15 +1276,19 @@ namespace build2
           pt = &link_member (*l, lo);
 
         if (pt->is_a<liba> () || pt->is_a<libs> ())
-          append_lib_options (args, *pt, "cxx.export.poptions", lo);
+          append_lib_options (args, *pt, lo,
+                              c_export_poptions,
+                              x_export_poptions);
       }
 
-      append_options (args, t, "cxx.poptions");
-      append_options (args, t, "cxx.coptions");
+      append_options (args, t, c_poptions);
+      append_options (args, t, x_poptions);
+      append_options (args, t, c_coptions);
+      append_options (args, t, x_coptions);
 
       string std, out, out1; // Storage.
 
-      append_std (args, rs, cid, t, std);
+      append_std (args, rs, t, std);
 
       if (cid == "msvc")
       {
@@ -1311,7 +1296,7 @@ namespace build2
         // in VS2013/12.0. Why do we bother? Because the command line suddenly
         // becomes readable.
         //
-        uint64_t cver (cast<uint64_t> (rs["cxx.version.major"]));
+        uint64_t ver (cast<uint64_t> (rs[x_version_major]));
 
         args.push_back ("/nologo");
 
@@ -1322,7 +1307,10 @@ namespace build2
         // see any relevant options explicitly specified, we take our hands
         // off.
         //
-        if (!find_option_prefix ("/EH", args))
+        // For C looks like no /EH* (exceptions supported but no C++ objects
+        // destroyed) is a reasonable default.
+        //
+        if (x_lang == lang::cxx && !find_option_prefix ("/EH", args))
           args.push_back ("/EHsc");
 
         // The runtime is a bit more interesting. At first it may seem like a
@@ -1363,7 +1351,7 @@ namespace build2
         //
         if (find_options ({"/Zi", "/ZI"}, args))
         {
-          if (cver >= 18)
+          if (ver >= 18)
             args.push_back ("/Fd:");
           else
             out1 = "/Fd";
@@ -1374,7 +1362,7 @@ namespace build2
           args.push_back (out1.c_str ());
         }
 
-        if (cver >= 18)
+        if (ver >= 18)
         {
           args.push_back ("/Fo:");
           args.push_back (relo.string ().c_str ());
@@ -1385,8 +1373,8 @@ namespace build2
           args.push_back (out.c_str ());
         }
 
-        args.push_back ("/c");  // Compile only.
-        args.push_back ("/TP"); // Compile as C++.
+        args.push_back ("/c");                              // Compile only.
+        args.push_back (x_lang == lang::c ? "/TC" : "/TP"); // Compile as.
         args.push_back (rels.string ().c_str ());
       }
       else
@@ -1411,7 +1399,7 @@ namespace build2
       if (verb >= 2)
         print_process (args);
       else if (verb)
-        text << "c++ " << *s;
+        text << x_name << ' ' << *s;
 
       try
       {
@@ -1475,13 +1463,10 @@ namespace build2
     }
 
     target_state compile::
-    perform_clean (action a, target& xt)
+    perform_clean (action a, target& xt) const
     {
       file& t (static_cast<file&> (xt));
 
-      scope& rs (t.root_scope ());
-      const string& cid (cast<string> (rs["cxx.id"]));
-
       initializer_list<const char*> e;
 
       if (cid == "msvc")
@@ -1491,7 +1476,5 @@ namespace build2
 
       return clean_extra (a, t, e);
     }
-
-    compile compile::instance;
   }
 }
diff --git a/build2/cxx/guess b/build2/cc/guess
index 63858ad..977e081 100644
--- a/build2/cxx/guess
+++ b/build2/cc/guess
@@ -1,28 +1,29 @@
-// file      : build2/cxx/guess -*- C++ -*-
+// file      : build2/cc/guess -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#ifndef BUILD2_CXX_GUESS
-#define BUILD2_CXX_GUESS
+#ifndef BUILD2_CC_GUESS
+#define BUILD2_CC_GUESS
 
 #include <build2/types>
 #include <build2/utility>
 
+#include <build2/cc/types>
+
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
-    // C++ compiler id consisting of a type and optional variant. If the
-    // variant is not empty, then the id is spelled out as 'type-variant',
-    // similar to target triplets (this also means that the type cannot
-    // contain '-').
+    // Compiler id consisting of a type and optional variant. If the variant
+    // is not empty, then the id is spelled out as 'type-variant', similar to
+    // target triplets (this also means that the type cannot contain '-').
     //
     // Currently recognized compilers and their ids:
     //
-    // gcc          GCC g++
-    // clang        Vanilla Clang clang++
-    // clang-apple  Apple Clang clang++ and the g++ "alias"
-    // icc          Intel icpc
+    // gcc          GCC gcc/g++
+    // clang        Vanilla Clang clang/clang++
+    // clang-apple  Apple Clang clang/clang++ and the gcc/g++ "alias"
+    // icc          Intel icc/icpc
     // msvc         Microsoft cl.exe
     //
     struct compiler_id
@@ -43,8 +44,8 @@ namespace build2
       return os << id.string ();
     }
 
-    // C++ compiler version. Here we map the various compiler version formats
-    // to something that resembles the MAJOR.MINOR.PATCH-BUILD form of the
+    // Compiler version. Here we map the various compiler version formats to
+    // something that resembles the MAJOR.MINOR.PATCH-BUILD form of the
     // Semantic Versioning. While the MAJOR.MINOR part is relatively
     // straightforward, PATCH may be empty and BUILD can contain pretty much
     // anything (including spaces).
@@ -74,7 +75,7 @@ namespace build2
       std::string build;
     };
 
-    // C++ compiler information.
+    // Compiler information.
     //
     // The signature is normally the -v/--version line that was used to guess
     // the compiler id and its version.
@@ -95,6 +96,9 @@ namespace build2
     // unlike all the preceding fields, this one takes into account the
     // compile options (e.g., -m32).
     //
+    // The pattern is the toolchain program pattern that could sometimes be
+    // derived for some toolchains. For example, i686-w64-mingw32-*.
+    //
     struct compiler_info
     {
       compiler_id id;
@@ -102,11 +106,20 @@ namespace build2
       string signature;
       string checksum;
       string target;
+      string pattern;
     };
 
+    // In a sense this is analagous to the language standard which we handle
+    // via a virtual function in common. However, duplicating this hairy ball
+    // of fur in multiple places doesn't seem wise, especially considering
+    // that most of it will be the same, at least for C and C++.
+    //
     compiler_info
-    guess (const path& cxx, const strings* coptions);
+    guess (lang,
+           const path& xc,
+           const strings* c_coptions,
+           const strings* x_coptions);
   }
 }
 
-#endif // BUILD2_CXX_GUESS
+#endif // BUILD2_CC_GUESS
diff --git a/build2/cxx/guess.cxx b/build2/cc/guess.cxx
index 11a832c..d80dddd 100644
--- a/build2/cxx/guess.cxx
+++ b/build2/cc/guess.cxx
@@ -1,8 +1,8 @@
-// file      : build2/cxx/guess.cxx -*- C++ -*-
+// file      : build2/cc/guess.cxx -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#include <build2/cxx/guess>
+#include <build2/cc/guess>
 
 #include <cstring>  // strlen()
 
@@ -12,7 +12,7 @@ using namespace std;
 
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
     // Pre-guess the compiler type based on the compiler executable name.
     // Return empty string if can't make a guess (for example, because the
@@ -20,11 +20,11 @@ namespace build2
     // not the variant.
     //
     static string
-    pre_guess (const path& cxx)
+    pre_guess (lang xl, const path& xc)
     {
-      tracer trace ("cxx::pre_guess");
+      tracer trace ("cc::pre_guess");
 
-      const string s (cxx.leaf ().base ().string ());
+      const string s (xc.leaf ().base ().string ());
       size_t n (s.size ());
 
       // Name separator characters (e.g., '-' in 'g++-4.8').
@@ -44,39 +44,55 @@ namespace build2
           ((p += m) == n || sep (s[p])); // Separated at the end.
       };
 
-      if (stem ("g++"))
-        return "gcc";
+      // Warn if the user specified a C compiler instead of C++ or vice versa.
+      //
+      lang o;                   // Other language.
+      const char* as (nullptr); // Actual stem.
+      const char* es (nullptr); // Expected stem.
 
-      if (stem ("clang++"))
-        return "clang";
+      switch (xl)
+      {
+      case lang::c:
+        {
+          // Keep msvc last since 'cl' is very generic.
+          //
+          if (stem ("gcc"))   return "gcc";
+          if (stem ("clang")) return "clang";
+          if (stem ("icc"))   return "icc";
+          if (stem ("cl"))    return "msvc";
 
-      if (stem ("icpc"))
-        return "icc";
+          if      (stem (as = "g++"))     es = "gcc";
+          else if (stem (as = "clang++")) es = "clang";
+          else if (stem (as = "icpc"))    es = "icc";
+          else if (stem (as = "c++"))     es = "cc";
 
-      // Keep this one last since 'cl' is very generic.
-      //
-      if (stem ("cl"))
-        return "msvc";
+          o = lang::cxx;
+          break;
+        }
+      case lang::cxx:
+        {
+          // Keep msvc last since 'cl' is very generic.
+          //
+          if (stem ("g++"))     return "gcc";
+          if (stem ("clang++")) return "clang";
+          if (stem ("icpc"))    return "icc";
+          if (stem ("cl"))      return "msvc";
 
-      // Warn if the user specified a C compiler instead of C++.
-      //
-      if (stem ("gcc"))
-      {
-        warn << cxx << " looks like a C compiler" <<
-          info << "should it be 'g++' instead of 'gcc'?";
-      }
-      else if (stem ("clang"))
-      {
-        warn << cxx << " looks like a C compiler" <<
-          info << "should it be 'clang++' instead of 'clang'?";
-      }
-      else if (stem ("icc"))
-      {
-        warn << cxx << " looks like a C compiler" <<
-          info << "should it be 'icpc' instead of 'icc'?";
+          if      (stem (as = "gcc"))   es = "g++";
+          else if (stem (as = "clang")) es = "clang++";
+          else if (stem (as = "icc"))   es = "icpc";
+          else if (stem (as = "cc"))    es = "c++";
+
+          o = lang::c;
+          break;
+        }
       }
 
-      l4 ([&]{trace << "unable to guess compiler type of " << cxx;});
+      if (es != nullptr)
+        warn << xc << " looks like a " << o << " compiler" <<
+          info << "should it be '" << es << "' instead of '" << as << "'?";
+
+      l4 ([&]{trace << "unable to guess  compiler type of " << xc;});
       return "";
     }
 
@@ -95,9 +111,9 @@ namespace build2
     };
 
     static guess_result
-    guess (const path& cxx, const string& pre)
+    guess (lang, const path& xc, const string& pre)
     {
-      tracer trace ("cxx::guess");
+      tracer trace ("cc::guess");
 
       guess_result r;
 
@@ -120,7 +136,8 @@ namespace build2
       {
         auto f = [] (string& l) -> guess_result
         {
-          // The g++ -v output will have a line (currently last) in the form:
+          // The gcc/g++ -v output will have a line (currently last) in the
+          // form:
           //
           // "gcc version X.Y.Z ..."
           //
@@ -137,8 +154,8 @@ namespace build2
           if (l.compare (0, 4, "gcc ") == 0)
             return guess_result {{"gcc", ""}, move (l), ""};
 
-          // The Apple clang++ -v output will have a line (currently first)
-          // in the form:
+          // The Apple clang/clang++ -v output will have a line (currently
+          // first) in the form:
           //
           // "Apple (LLVM|clang) version X.Y.Z ..."
           //
@@ -155,19 +172,20 @@ namespace build2
           // Apple LLVM version 7.0.2 (clang-700.1.81)
           // Apple LLVM version 7.3.0 (clang-703.0.16.1)
           //
-          // Note that the g++ "alias" for clang++ also includes this line
-          // but it is (currently) preceded by "Configured with: ...".
+          // Note that the gcc/g++ "aliases" for clang/clang++ also include
+          // this line but it is (currently) preceded by "Configured with:
+          // ...".
           //
-          // Check for Apple clang before the vanilla one since the above
-          // line also includes "clang".
+          // Check for Apple clang before the vanilla one since the above line
+          // also includes "clang".
           //
           if (l.compare (0, 6, "Apple ") == 0 &&
               (l.compare (6, 5, "LLVM ") == 0 ||
                l.compare (6, 6, "clang ") == 0))
             return guess_result {{"clang", "apple"}, move (l), ""};
 
-          // The vanilla clang++ -v output will have a line (currently first)
-          // in the form:
+          // The vanilla clang/clang++ -v output will have a line (currently
+          // first) in the form:
           //
           // "[... ]clang version X.Y.Z[-...] ..."
           //
@@ -189,12 +207,16 @@ namespace build2
         // clang) which makes sense to include into the compiler checksum. So
         // ask run() to calculate it for every line of the -v ouput.
         //
+        // One notable consequence of this is that if the locale changes
+        // (e.g., via LC_ALL), then the compiler signature will most likely
+        // change as well because of the translated text.
+        //
         sha256 cs;
 
         // Suppress all the compiler errors because we may be trying an
         // unsupported option.
         //
-        r = run<guess_result> (cxx, "-v", f, false, false, &cs);
+        r = run<guess_result> (xc, "-v", f, false, false, &cs);
 
         if (!r.empty ())
           r.checksum = cs.string ();
@@ -214,6 +236,7 @@ namespace build2
           // icpc (ICC) 14.0.0 20130728
           // icpc (ICC) 15.0.2 20150121
           // icpc (ICC) 16.0.2 20160204
+          // icc (ICC) 16.0.2 20160204
           //
           if (l.find (" (ICC) ") != string::npos)
             return guess_result {{"icc", ""}, move (l), ""};
@@ -221,7 +244,7 @@ namespace build2
           return guess_result ();
         };
 
-        r = run<guess_result> (cxx, "--version", f, false);
+        r = run<guess_result> (xc, "--version", f, false);
       }
 
       // Finally try to run it without any options to detect msvc.
@@ -253,7 +276,7 @@ namespace build2
           return guess_result ();
         };
 
-        r = run<guess_result> (cxx, f, false);
+        r = run<guess_result> (xc, f, false);
       }
 
       if (!r.empty ())
@@ -267,19 +290,23 @@ namespace build2
           r = guess_result ();
         }
         else
-          l5 ([&]{trace << cxx << " is " << r.id << ": '"
+          l5 ([&]{trace << xc << " is " << r.id << ": '"
                         << r.signature << "'";});
       }
       else
-        l4 ([&]{trace << "unable to determine compiler type of " << cxx;});
+        l4 ([&]{trace << "unable to determine compiler type of " << xc;});
 
       return r;
     }
 
     static compiler_info
-    guess_gcc (const path& cxx, const strings* coptions, guess_result&& gr)
+    guess_gcc (lang,
+               const path& xc,
+               const strings* c_coptions,
+               const strings* x_coptions,
+               guess_result&& gr)
     {
-      tracer trace ("cxx::guess_gcc");
+      tracer trace ("cc::guess_gcc");
 
       // Extract the version. The signature line has the following format
       // though language words can be translated and even rearranged (see
@@ -356,9 +383,9 @@ namespace build2
       // multi-arch support), then use the result. Otherwise, fallback to
       // -dumpmachine (older gcc or not multi-arch).
       //
-      cstrings args {cxx.string ().c_str (), "-print-multiarch"};
-      if (coptions != nullptr)
-        append_options (args, *coptions);
+      cstrings args {xc.string ().c_str (), "-print-multiarch"};
+      if (c_coptions != nullptr) append_options (args, *c_coptions);
+      if (x_coptions != nullptr) append_options (args, *x_coptions);
       args.push_back (nullptr);
 
       // The output of both -print-multiarch and -dumpmachine is a single line
@@ -370,7 +397,7 @@ namespace build2
 
       if (t.empty ())
       {
-        l5 ([&]{trace << cxx << " doesn's support -print-multiarch, "
+        l5 ([&]{trace << xc << " doesn's support -print-multiarch, "
                       << "falling back to -dumpmachine";});
 
         args[1] = "-dumpmachine";
@@ -378,7 +405,7 @@ namespace build2
       }
 
       if (t.empty ())
-        fail << "unable to extract target architecture from " << cxx
+        fail << "unable to extract target architecture from " << xc
              << " -print-multiarch or -dumpmachine output";
 
       return compiler_info {
@@ -386,11 +413,16 @@ namespace build2
         move (v),
         move (gr.signature),
         move (gr.checksum), // Calculated on whole -v output.
-        move (t)};
+        move (t),
+        string ()};
     }
 
     static compiler_info
-    guess_clang (const path& cxx, const strings* coptions, guess_result&& gr)
+    guess_clang (lang,
+                 const path& xc,
+                 const strings* c_coptions,
+                 const strings* x_coptions,
+                 guess_result&& gr)
     {
       // Extract the version. Here we will try to handle both vanilla and
       // Apple clang since the signature lines are fairly similar. They have
@@ -466,9 +498,9 @@ namespace build2
       // Unlike gcc, clang doesn't have -print-multiarch. Its -dumpmachine,
       // however, respects the compile options (e.g., -m32).
       //
-      cstrings args {cxx.string ().c_str (), "-dumpmachine"};
-      if (coptions != nullptr)
-        append_options (args, *coptions);
+      cstrings args {xc.string ().c_str (), "-dumpmachine"};
+      if (c_coptions != nullptr) append_options (args, *c_coptions);
+      if (x_coptions != nullptr) append_options (args, *x_coptions);
       args.push_back (nullptr);
 
       // The output of -dumpmachine is a single line containing just the
@@ -477,7 +509,7 @@ namespace build2
       string t (run<string> (args.data (), [] (string& l) {return move (l);}));
 
       if (t.empty ())
-        fail << "unable to extract target architecture from " << cxx
+        fail << "unable to extract target architecture from " << xc
              << " -dumpmachine output";
 
       return compiler_info {
@@ -485,11 +517,16 @@ namespace build2
         move (v),
         move (gr.signature),
         move (gr.checksum), // Calculated on whole -v output.
-        move (t)};
+        move (t),
+        string ()};
     }
 
     static compiler_info
-    guess_icc (const path& cxx, const strings* coptions, guess_result&& gr)
+    guess_icc (lang xl,
+               const path& xc,
+               const strings* c_coptions,
+               const strings* x_coptions,
+               guess_result&& gr)
     {
       // Extract the version. If the version has the fourth component, then
       // the signature line (extracted with --version) won't include it. So we
@@ -511,6 +548,7 @@ namespace build2
       // Intel(R) C++ Intel(R) 64 Compiler for applications running on Intel(R) 64, Version 16.0.2.181 Build 20160204
       // Intel(R) C++ Intel(R) 64 Compiler for applications running on IA-32, Version 16.0.2.181 Build 20160204
       // Intel(R) C++ Intel(R) 64 Compiler for applications running on Intel(R) MIC Architecture, Version 16.0.2.181 Build 20160204
+      // Intel(R) C Intel(R) 64 Compiler for applications running on Intel(R) MIC Architecture, Version 16.0.2.181 Build 20160204
       //
       // We should probably also assume the language words can be translated
       // and even rearranged.
@@ -527,13 +565,14 @@ namespace build2
 
       // The -V output is sent to STDERR.
       //
-      s = run<string> (cxx, "-V", f, false);
+      s = run<string> (xc, "-V", f, false);
 
       if (s.empty ())
-        fail << "unable to extract signature from " << cxx << " -V output";
+        fail << "unable to extract signature from " << xc << " -V output";
 
-      if (s.find ("C++") == string::npos)
-        fail << cxx << " does not appear to be the Intel C++ compiler" <<
+      if (s.find (xl == lang::c ? " C " : " C++ ") == string::npos)
+        fail << xc << " does not appear to be the Intel " << xl
+             << " compiler" <<
           info << "extracted signature: '" << s << "'";
 
       // Scan the string as words and look for the version. It consist of only
@@ -619,9 +658,9 @@ namespace build2
       // "Intel(R)" "64"
       // "Intel(R)" "MIC"      (-dumpmachine says: x86_64-k1om-linux)
       //
-      cstrings args {cxx.string ().c_str (), "-V"};
-      if (coptions != nullptr)
-        append_options (args, *coptions);
+      cstrings args {xc.string ().c_str (), "-V"};
+      if (c_coptions != nullptr) append_options (args, *c_coptions);
+      if (x_coptions != nullptr) append_options (args, *x_coptions);
       args.push_back (nullptr);
 
       // The -V output is sent to STDERR.
@@ -629,7 +668,7 @@ namespace build2
       string t (run<string> (args.data (), f, false));
 
       if (t.empty ())
-        fail << "unable to extract target architecture from " << cxx
+        fail << "unable to extract target architecture from " << xc
              << " -V output";
 
       string arch;
@@ -668,10 +707,10 @@ namespace build2
       // on which we are running), who knows what will happen in the future.
       // So instead we are going to use -dumpmachine and substitute the CPU.
       //
-      t = run<string> (cxx, "-dumpmachine", [] (string& l) {return move (l);});
+      t = run<string> (xc, "-dumpmachine", [] (string& l) {return move (l);});
 
       if (t.empty ())
-        fail << "unable to extract target architecture from " << cxx
+        fail << "unable to extract target architecture from " << xc
              << " -dumpmachine output";
 
       // The first component in the triplet is always CPU.
@@ -692,11 +731,16 @@ namespace build2
         move (v),
         move (gr.signature),
         cs.string (),
-        move (arch)};
+        move (arch),
+        string ()};
     }
 
     static compiler_info
-    guess_msvc (const path&, guess_result&& gr)
+    guess_msvc (lang,
+                const path& xc,
+                const strings*,
+                const strings*,
+                guess_result&& gr)
     {
       // Extract the version. The signature line has the following format
       // though language words can be translated and even rearranged (see
@@ -815,9 +859,9 @@ namespace build2
       //
       // The (toolchain) VENDOR is also straightforward: 'microsoft'. Why not
       // omit it? Two reasons: firstly, there are other compilers with the
-      // otherwise same target, for example Intel C++, and it could be useful
-      // to distinguish between them. Secondly, by having all four components
-      // we remove any parsing ambiguity.
+      // otherwise same target, for example Intel C/C++, and it could be
+      // useful to distinguish between them. Secondly, by having all four
+      // components we remove any parsing ambiguity.
       //
       // OS-ABI is where things are not as clear cut. The OS part shouldn't
       // probably be just 'windows' since we have Win32 and WinCE. And WinRT.
@@ -881,6 +925,31 @@ namespace build2
                   << "' to runtime version";
       }
 
+      // Derive the toolchain pattern.
+      //
+      // If the compiler name is/starts with 'cl' (e.g., cl.exe, cl-14),
+      // then replace it with '*' and use it as a pattern for lib, link,
+      // etc.
+      //
+      string pat;
+
+      if (xc.size () > 2)
+      {
+        const string& l (xc.leaf ().string ());
+        size_t n (l.size ());
+
+        if (n >= 2 &&
+            (l[0] == 'c' || l[0] == 'C') &&
+            (l[1] == 'l' || l[1] == 'L') &&
+            (n == 2 || l[2] == '.' || l[2] == '-'))
+        {
+          path p (xc.directory ());
+          p /= "*";
+          p += l.c_str () + 2;
+          pat = move (p).string ();
+        }
+      }
+
       // Use the signature line to generate the checksum.
       //
       sha256 cs (s);
@@ -890,13 +959,17 @@ namespace build2
         move (v),
         move (gr.signature),
         cs.string (),
-        move (arch)};
+        move (arch),
+        move (pat)};
     }
 
     compiler_info
-    guess (const path& cxx, const strings* coptions)
+    guess (lang xl,
+           const path& xc,
+           const strings* c_coptions,
+           const strings* x_coptions)
     {
-      string pre (pre_guess (cxx));
+      string pre (pre_guess (xl, xc));
       guess_result gr;
 
       // If we could pre-guess the type based on the excutable name, then
@@ -904,45 +977,76 @@ namespace build2
       //
       if (!pre.empty ())
       {
-        gr = guess (cxx, pre);
+        gr = guess (xl, xc, pre);
 
         if (gr.empty ())
-          warn << cxx << " name looks like " << pre << " but it is not";
+          warn << xc << " name looks like " << pre << " but it is not";
       }
 
       if (gr.empty ())
-        gr = guess (cxx, "");
+        gr = guess (xl, xc, "");
 
       if (gr.empty ())
-        fail << "unable to guess C++ compiler type of " << cxx;
+        fail << "unable to guess " << xl << " compiler type of " << xc;
 
+      compiler_info r;
       const compiler_id& id (gr.id);
 
       if (id.type == "gcc")
       {
         assert (id.variant.empty ());
-        return guess_gcc (cxx, coptions, move (gr));
+        r = guess_gcc (xl, xc, c_coptions, x_coptions, move (gr));
       }
       else if (id.type == "clang")
       {
         assert (id.variant.empty () || id.variant == "apple");
-        return guess_clang (cxx, coptions, move (gr));
+        r = guess_clang (xl, xc, c_coptions, x_coptions, move (gr));
       }
       else if (id.type == "icc")
       {
         assert (id.variant.empty ());
-        return guess_icc (cxx, coptions, move (gr));
+        r = guess_icc (xl, xc, c_coptions, x_coptions, move (gr));
       }
       else if (id.type == "msvc")
       {
         assert (id.variant.empty ());
-        return guess_msvc (cxx, move (gr));
+        r = guess_msvc (xl, xc, c_coptions, x_coptions, move (gr));
       }
       else
-      {
         assert (false);
-        return compiler_info ();
+
+      // Derive binutils pattern unless this has already been done by the
+      // compiler-specific code.
+      //
+      if (r.pattern.empty ())
+      {
+        // When cross-compiling the whole toolchain is normally prefixed with
+        // the target triplet, e.g., x86_64-w64-mingw32-{gcc,g++,ar,ld}.
+        //
+        // BTW, for GCC we also get gcc-{ar,ranlib} which add support for the
+        // LTO plugin though it seems more recent GNU binutils (2.25) are able
+        // to load the plugin when needed automatically. So it doesn't seem we
+        // should bother trying to support this on our end (one way we could
+        // do it is by passing config.bin.{ar,ranlib} as hints).
+        //
+        const string& t (r.target);
+        size_t n (t.size ());
+
+        if (xc.size () > n + 1)
+        {
+          const string& l (xc.leaf ().string ());
+
+          if (l.size () > n + 1 && l.compare (0, n, t) == 0 && l[n] == '-')
+          {
+            path p (xc.directory ());
+            p /= t;
+            p += "-*";
+            r.pattern = move (p).string ();
+          }
+        }
       }
+
+      return r;
     }
   }
 }
diff --git a/build2/cc/init b/build2/cc/init
new file mode 100644
index 0000000..d8ebd0e
--- /dev/null
+++ b/build2/cc/init
@@ -0,0 +1,55 @@
+// file      : build2/cc/init -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_CC_INIT
+#define BUILD2_CC_INIT
+
+#include <build2/types>
+#include <build2/utility>
+
+#include <build2/module>
+
+namespace build2
+{
+  namespace cc
+  {
+    bool
+    vars_init (scope&,
+               scope&,
+               const location&,
+               unique_ptr<module_base>&,
+               bool,
+               bool,
+               const variable_map&);
+
+    bool
+    config_init (scope&,
+                 scope&,
+                 const location&,
+                 unique_ptr<module_base>&,
+                 bool,
+                 bool,
+                 const variable_map&);
+
+    bool
+    core_init (scope&,
+               scope&,
+               const location&,
+               unique_ptr<module_base>&,
+               bool,
+               bool,
+               const variable_map&);
+
+    bool
+    init (scope&,
+          scope&,
+          const location&,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&);
+  }
+}
+
+#endif // BUILD2_CC_INIT
diff --git a/build2/cc/init.cxx b/build2/cc/init.cxx
new file mode 100644
index 0000000..2623c79
--- /dev/null
+++ b/build2/cc/init.cxx
@@ -0,0 +1,321 @@
+// file      : build2/cc/init.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <build2/cc/init>
+
+#include <butl/triplet>
+
+#include <build2/scope>
+#include <build2/context>
+#include <build2/diagnostics>
+
+#include <build2/config/utility>
+
+#include <build2/cc/target>
+
+using namespace std;
+using namespace butl;
+
+namespace build2
+{
+  namespace cc
+  {
+    bool
+    vars_init (scope& r,
+               scope&,
+               const location&,
+               unique_ptr<module_base>&,
+               bool first,
+               bool,
+               const variable_map&)
+    {
+      tracer trace ("cc::vars_init");
+      l5 ([&]{trace << "for " << r.out_path ();});
+
+      assert (first);
+
+      // Enter variables. Note: some overridable, some not.
+      //
+      auto& v (var_pool);
+
+      v.insert<strings> ("config.cc.poptions", true);
+      v.insert<strings> ("config.cc.coptions", true);
+      v.insert<strings> ("config.cc.loptions", true);
+      v.insert<strings> ("config.cc.libs",     true);
+
+      v.insert<strings> ("cc.poptions");
+      v.insert<strings> ("cc.coptions");
+      v.insert<strings> ("cc.loptions");
+      v.insert<strings> ("cc.libs");
+
+      v.insert<strings> ("cc.export.poptions");
+      v.insert<strings> ("cc.export.coptions");
+      v.insert<strings> ("cc.export.loptions");
+      v.insert<strings> ("cc.export.libs");
+
+      // Hint variables (not overridable).
+      //
+      v.insert<string> ("config.cc.id");
+      v.insert<string> ("config.cc.target");
+      v.insert<string> ("config.cc.pattern");
+
+      return true;
+    }
+
+    bool
+    config_init (scope& r,
+                 scope& b,
+                 const location& loc,
+                 unique_ptr<module_base>&,
+                 bool first,
+                 bool,
+                 const variable_map& hints)
+    {
+      tracer trace ("cc::config_init");
+      l5 ([&]{trace << "for " << b.out_path ();});
+
+      // Load cc.vars.
+      //
+      if (first)
+      {
+        if (!cast_false<bool> (b["cc.vars.loaded"]))
+          load_module ("cc.vars", r, b, loc);
+      }
+
+      // Configure.
+      //
+      if (first)
+      {
+        // config.cc.id
+        //
+        {
+          // This value must be hinted.
+          //
+          r.assign<string> ("cc.id") = cast<string> (hints["config.cc.id"]);
+        }
+
+        // config.cc.target
+        //
+        {
+          // This value must be hinted and already canonicalized.
+          //
+          const string& s (cast<string> (hints["config.cc.target"]));
+
+          try
+          {
+            //@@ We do it in the hinting module and here. Any way not to
+            //   duplicate the effort? Maybe move the splitting here and
+            //   simply duplicate the values there?
+            //
+            triplet t (s);
+
+            // Enter as cc.target.{cpu,vendor,system,version,class}.
+            //
+            r.assign<string> ("cc.target") = s;
+            r.assign<string> ("cc.target.cpu") = move (t.cpu);
+            r.assign<string> ("cc.target.vendor") = move (t.vendor);
+            r.assign<string> ("cc.target.system") = move (t.system);
+            r.assign<string> ("cc.target.version") = move (t.version);
+            r.assign<string> ("cc.target.class") = move (t.class_);
+          }
+          catch (const invalid_argument& e)
+          {
+            assert (false); // Should have been caught by the hinting module.
+          }
+        }
+
+        // config.cc.pattern
+        //
+        {
+          // This value could be hinted.
+          //
+          if (auto l = hints["config.cc.pattern"])
+            r.assign<string> ("cc.pattern") = cast<string> (l);
+        }
+
+        // Note that we are not having a config report since it will just
+        // duplicate what has already been printed by the hinting module.
+      }
+
+      // config.cc.{p,c,l}options
+      // config.cc.libs
+      //
+      // @@ Same nonsense as in module.
+      //
+      //
+      b.assign ("cc.poptions") += cast_null<strings> (
+        config::optional (r, "config.cc.poptions"));
+
+      b.assign ("cc.coptions") += cast_null<strings> (
+        config::optional (r, "config.cc.coptions"));
+
+      b.assign ("cc.loptions") += cast_null<strings> (
+        config::optional (r, "config.cc.loptions"));
+
+      b.assign ("cc.libs") += cast_null<strings> (
+        config::optional (r, "config.cc.libs"));
+
+      // Load the bin.config module.
+      //
+      if (!cast_false<bool> (b["bin.config.loaded"]))
+      {
+        // Prepare configuration hints. They are only used on the first load
+        // of bin.config so we only populate them on our first load.
+        //
+        variable_map h;
+        if (first)
+        {
+          h.assign ("config.bin.target") = cast<string> (r["cc.target"]);
+          if (auto l = r["cc.pattern"])
+            h.assign ("config.bin.pattern") = cast<string> (l);
+        }
+
+        load_module ("bin.config", r, b, loc, false, h);
+      }
+
+      // Verify bin's target matches ours (we do it even if we loaded it
+      // ourselves since the target can come from the configuration and not
+      // our hint).
+      //
+      if (first)
+      {
+        const string& ct (cast<string> (r["cc.target"]));
+        const string& bt (cast<string> (r["bin.target"]));
+
+        if (bt != ct)
+          fail (loc) << "cc and bin module target mismatch" <<
+            info << "cc.target is " << ct <<
+            info << "bin.target is " << bt;
+      }
+
+      const string& cid (cast<string> (r["cc.id"]));
+      const string& tsys (cast<string> (r["cc.target.system"]));
+
+      // Load bin.*.config for bin.* modules we may need (see core_init()
+      // below).
+      //
+      if (auto l = r["config.bin.lib"])
+      {
+        if (cast<string> (l) != "shared")
+        {
+          if (!cast_false<bool> (b["bin.ar.config.loaded"]))
+            load_module ("bin.ar.config", r, b, loc);
+        }
+      }
+
+      if (cid == "msvc")
+      {
+        if (!cast_false<bool> (b["bin.ld.config.loaded"]))
+          load_module ("bin.ld.config", r, b, loc);
+      }
+
+      if (tsys == "mingw32")
+      {
+        if (!cast_false<bool> (b["bin.rc.config.loaded"]))
+          load_module ("bin.rc.config", r, b, loc);
+      }
+
+      return true;
+    }
+
+    bool
+    core_init (scope& r,
+               scope& b,
+               const location& loc,
+               unique_ptr<module_base>&,
+               bool,
+               bool,
+               const variable_map& hints)
+    {
+      tracer trace ("cc::core_init");
+      l5 ([&]{trace << "for " << b.out_path ();});
+
+      // Load cc.config.
+      //
+      if (!cast_false<bool> (b["cc.config.loaded"]))
+        load_module ("cc.config", r, b, loc, false, hints);
+
+      // Load the bin module.
+      //
+      if (!cast_false<bool> (b["bin.loaded"]))
+        load_module ("bin", r, b, loc);
+
+      const string& cid (cast<string> (r["cc.id"]));
+      const string& tsys (cast<string> (r["cc.target.system"]));
+
+      // Load the bin.ar module unless we were asked to only build shared
+      // libraries.
+      //
+      if (auto l = r["config.bin.lib"])
+      {
+        if (cast<string> (l) != "shared")
+        {
+          if (!cast_false<bool> (b["bin.ar.loaded"]))
+            load_module ("bin.ar", r, b, loc);
+        }
+      }
+
+      // In the VC world you link things directly with link.exe so load the
+      // bin.ld module.
+      //
+      if (cid == "msvc")
+      {
+        if (!cast_false<bool> (b["bin.ld.loaded"]))
+          load_module ("bin.ld", r, b, loc);
+      }
+
+      // If our target is MinGW, then we will need the resource compiler
+      // (windres) in order to embed manifests into executables.
+      //
+      if (tsys == "mingw32")
+      {
+        if (!cast_false<bool> (b["bin.rc.loaded"]))
+          load_module ("bin.rc", r, b, loc);
+      }
+
+      return true;
+    }
+
+    bool
+    init (scope& r,
+          scope& b,
+          const location& loc,
+          unique_ptr<module_base>&,
+          bool,
+          bool,
+          const variable_map&)
+    {
+      tracer trace ("cc::init");
+      l5 ([&]{trace << "for " << b.out_path ();});
+
+      // This module is an "alias" for c.config and cxx.config. Its intended
+      // use is to make sure that the C/C++ configuration is captured in an
+      // amalgamation rather than subprojects.
+      //
+      // We want to order the loading to match what user specified on the
+      // command line (config.c or config.cxx). This way the first loaded
+      // module (with user-specified config.*) will hint the compiler to the
+      // second.
+      //
+      bool lc (!cast_false<bool> (b["c.config.loaded"]));
+      bool lp (!cast_false<bool> (b["cxx.config.loaded"]));
+
+      // If none of them are already loaded, load c first only if config.c
+      // is specified.
+      //
+      if (lc && lp && r["config.c"])
+      {
+        load_module ("c.config", r, b, loc);
+        load_module ("cxx.config", r, b, loc);
+      }
+      else
+      {
+        if (lp) load_module ("cxx.config", r, b, loc);
+        if (lc) load_module ("c.config", r, b, loc);
+      }
+
+      return true;
+    }
+  }
+}
diff --git a/build2/cxx/install b/build2/cc/install
index 119ef94..e2be905 100644
--- a/build2/cxx/install
+++ b/build2/cc/install
@@ -1,31 +1,39 @@
-// file      : build2/cxx/install -*- C++ -*-
+// file      : build2/cc/install -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#ifndef BUILD2_CXX_INSTALL
-#define BUILD2_CXX_INSTALL
+#ifndef BUILD2_CC_INSTALL
+#define BUILD2_CC_INSTALL
 
 #include <build2/types>
 #include <build2/utility>
 
 #include <build2/install/rule>
 
+#include <build2/cc/types>
+#include <build2/cc/common>
+
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
-    class install: public build2::install::file_rule
+    class link;
+
+    class install: public build2::install::file_rule, virtual common
     {
     public:
+      install (data&&, const link&);
+
       virtual target*
       filter (action, target&, prerequisite_member) const;
 
       virtual match_result
       match (action, target&, const string&) const;
 
-      static install instance;
+    private:
+      const link& link_;
     };
   }
 }
 
-#endif // BUILD2_CXX_INSTALL
+#endif // BUILD2_CC_INSTALL
diff --git a/build2/cxx/install.cxx b/build2/cc/install.cxx
index e07d115..b674886 100644
--- a/build2/cxx/install.cxx
+++ b/build2/cc/install.cxx
@@ -1,23 +1,25 @@
-// file      : build2/cxx/install.cxx -*- C++ -*-
+// file      : build2/cc/install.cxx -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#include <build2/cxx/install>
+#include <build2/cc/install>
 
 #include <build2/bin/target>
 
-#include <build2/cxx/link>
-#include <build2/cxx/common>
-#include <build2/cxx/target>
+#include <build2/cc/link>    // match()
+#include <build2/cc/utility>
 
 using namespace std;
 
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
     using namespace bin;
 
+    install::
+    install (data&& d, const link& l): common (move (d)), link_ (l) {}
+
     target* install::
     filter (action a, target& t, prerequisite_member p) const
     {
@@ -25,7 +27,7 @@ namespace build2
       {
         // Don't install executable's prerequisite headers.
         //
-        if (p.is_a<hxx> () || p.is_a<ixx> () || p.is_a<txx> () || p.is_a<h> ())
+        if (x_header (p))
           return nullptr;
       }
 
@@ -61,10 +63,8 @@ namespace build2
       // We only want to handle installation if we are also the
       // ones building this target. So first run link's match().
       //
-      match_result r (link::instance.match (a, t, hint));
+      match_result r (link_.match (a, t, hint));
       return r ? install::file_rule::match (a, t, "") : r;
     }
-
-    install install::instance;
   }
 }
diff --git a/build2/cc/link b/build2/cc/link
new file mode 100644
index 0000000..8be386f
--- /dev/null
+++ b/build2/cc/link
@@ -0,0 +1,78 @@
+// file      : build2/cc/link -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_CC_LINK
+#define BUILD2_CC_LINK
+
+#include <build2/types>
+#include <build2/utility>
+
+#include <build2/rule>
+
+#include <build2/bin/target>
+
+#include <build2/cc/types>
+#include <build2/cc/common>
+
+namespace build2
+{
+  namespace cc
+  {
+    class link: public rule, virtual common
+    {
+    public:
+      link (data&&);
+
+      virtual match_result
+      match (action, target&, const string& hint) const;
+
+      virtual recipe
+      apply (action, target&, const match_result&) const;
+
+      target_state
+      perform_update (action, target&) const;
+
+      target_state
+      perform_clean (action, target&) const;
+
+    private:
+      friend class compile;
+
+      // Extract system library search paths from GCC or compatible (Clang,
+      // Intel) using the -print-search-dirs option.
+      //
+      void
+      gcc_library_search_paths (scope&, dir_paths&) const;
+
+      // Extract system library search paths from VC (msvc.cxx).
+      //
+      void
+      msvc_library_search_paths (scope&, dir_paths&) const;
+
+      dir_paths
+      extract_library_paths (scope&) const;
+
+      // Alternative search logic for VC (msvc.cxx).
+      //
+      bin::liba*
+      msvc_search_static (const path&, const dir_path&, prerequisite&) const;
+
+      bin::libs*
+      msvc_search_shared (const path&, const dir_path&, prerequisite&) const;
+
+      target*
+      search_library (optional<dir_paths>&, prerequisite&) const;
+
+      // Windows-specific (windows-manifest.cxx).
+      //
+      path
+      windows_manifest (file&, bool rpath_assembly) const;
+
+    private:
+      const string rule_id;
+    };
+  }
+}
+
+#endif // BUILD2_CC_LINK
diff --git a/build2/cxx/link.cxx b/build2/cc/link.cxx
index d19d6b1..4bebc6f 100644
--- a/build2/cxx/link.cxx
+++ b/build2/cc/link.cxx
@@ -1,8 +1,8 @@
-// file      : build2/cxx/link.cxx -*- C++ -*-
+// file      : build2/cc/link.cxx -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#include <build2/cxx/link>
+#include <build2/cc/link>
 
 #include <cstdlib>  // exit()
 #include <iostream> // cerr
@@ -18,35 +18,43 @@
 #include <build2/diagnostics>
 
 #include <build2/bin/target>
-#include <build2/cxx/target>
 
-#include <build2/cxx/common>
-#include <build2/cxx/utility>
+#include <build2/cc/target>  // c
+#include <build2/cc/utility>
 
 using namespace std;
 using namespace butl;
 
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
     using namespace bin;
 
+    link::
+    link (data&& d)
+        : common (move (d)),
+          rule_id (string (x) += ".link 1")
+    {
+    }
+
     // Extract system library search paths from GCC or compatible (Clang,
-    // Intel C++) using the -print-search-dirs option.
+    // Intel) using the -print-search-dirs option.
     //
-    static void
-    gcc_library_search_paths (scope& bs, const string& cid, dir_paths& r)
+    void link::
+    gcc_library_search_paths (scope& bs, dir_paths& r) const
     {
       scope& rs (*bs.root_scope ());
 
       cstrings args;
-      string std_storage;
-
-      args.push_back (cast<path> (rs["config.cxx"]).string ().c_str ());
-      append_options (args, bs, "cxx.coptions");
-      append_std (args, rs, cid, bs, std_storage);
-      append_options (args, bs, "cxx.loptions");
+      string std; // Storage.
+
+      args.push_back (cast<path> (rs[config_x]).string ().c_str ());
+      append_options (args, bs, c_coptions);
+      append_options (args, bs, x_coptions);
+      append_std (args, rs, bs, std);
+      append_options (args, bs, c_loptions);
+      append_options (args, bs, x_loptions);
       args.push_back ("-print-search-dirs");
       args.push_back (nullptr);
 
@@ -80,7 +88,8 @@ namespace build2
         catch (const ifdstream::failure&)
         {
           pr.wait ();
-          fail << "error reading C++ compiler -print-search-dirs output";
+          fail << "error reading " << x_lang << " compiler -print-search-dirs "
+               << "output";
         }
       }
       catch (const process_error& e)
@@ -94,7 +103,8 @@ namespace build2
       }
 
       if (l.empty ())
-        fail << "unable to extract C++ compiler system library paths";
+        fail << "unable to extract " << x_lang << " compiler system library "
+             << "search paths";
 
       // Now the fun part: figuring out which delimiter is used. Normally it
       // is ':' but on Windows it is ';' (or can be; who knows for sure). Also
@@ -127,23 +137,16 @@ namespace build2
       }
     }
 
-    // Extract system library search paths from MSVC.
-    //
-    void
-    msvc_library_search_paths (scope&, const string&, dir_paths&); // msvc.cxx
-
     dir_paths link::
-    extract_library_paths (scope& bs)
+    extract_library_paths (scope& bs) const
     {
       dir_paths r;
-      scope& rs (*bs.root_scope ());
-      const string& cid (cast<string> (rs["cxx.id"]));
 
       // Extract user-supplied search paths (i.e., -L, /LIBPATH).
       //
-      if (auto l = bs["cxx.loptions"])
+      auto extract = [&r, this] (const value& val)
       {
-        const auto& v (cast<strings> (l));
+        const auto& v (cast<strings> (val));
 
         for (auto i (v.begin ()), e (v.end ()); i != e; ++i)
         {
@@ -184,28 +187,23 @@ namespace build2
           if (!d.relative ())
             r.push_back (move (d));
         }
-      }
+      };
+
+      if (auto l = bs[c_loptions]) extract (*l);
+      if (auto l = bs[x_loptions]) extract (*l);
 
       if (cid == "msvc")
-        msvc_library_search_paths (bs, cid, r);
+        msvc_library_search_paths (bs, r);
       else
-        gcc_library_search_paths (bs, cid, r);
+        gcc_library_search_paths (bs, r);
 
       return r;
     }
 
-    // Alternative search for VC (msvc.cxx).
-    //
-    liba*
-    msvc_search_static (const path& ld, const dir_path&, prerequisite&);
-
-    libs*
-    msvc_search_shared (const path& ld, const dir_path&, prerequisite&);
-
     target* link::
-    search_library (optional<dir_paths>& spc, prerequisite& p)
+    search_library (optional<dir_paths>& spc, prerequisite& p) const
     {
-      tracer trace ("cxx::link::search_library");
+      tracer trace (x, "link::search_library");
 
       // @@ This is hairy enough to warrant a separate implementation for
       //    Windows.
@@ -216,11 +214,6 @@ namespace build2
       if (p.target != nullptr)
         return p.target;
 
-      scope& rs (*p.scope.root_scope ());
-      const string& cid (cast<string> (rs["cxx.id"]));
-      const string& tsys (cast<string> (rs["cxx.target.system"]));
-      const string& tclass (cast<string> (rs["cxx.target.class"]));
-
       bool l (p.is_a<lib> ());
       const string* ext (l ? nullptr : p.ext); // Only for liba/libs.
 
@@ -426,6 +419,7 @@ namespace build2
         //
         if (cid == "msvc")
         {
+          scope& rs (*p.scope.root_scope ());
           const path& ld (cast<path> (rs["config.bin.ld"]));
 
           if (s == nullptr && !sn.empty ())
@@ -449,40 +443,42 @@ namespace build2
       // handle DLL export). The absence of either of these macros would mean
       // some other build system that cannot distinguish between the two.
       //
-      auto add_macro = [] (target& t, const char* suffix)
+      auto add_macro = [this] (target& t, const char* suffix)
       {
-        // If there is already a value, don't add anything, we don't want to
-        // be accumulating defines nor messing with custom values.
+        // If there is already a value (either in cc.export or x.export),
+        // don't add anything: we don't want to be accumulating defines nor
+        // messing with custom values. And if we are adding, then use the
+        // generic cc.export.
         //
-        auto p (t.vars.insert ("cxx.export.poptions"));
-
-        if (p.second)
+        if (!t.vars[x_export_poptions])
         {
-          // The "standard" macro name will be LIB<NAME>_{STATIC,SHARED},
-          // where <name> is the target name. Here we want to strike a balance
-          // between being unique and not too noisy.
-          //
-          string d ("-DLIB");
+          auto p (t.vars.insert (c_export_poptions));
 
-          auto upcase_sanitize = [] (char c) -> char
+          if (p.second)
           {
-            if (c == '-' || c == '+' || c == '.')
-              return '_';
-            else
-              return ucase (c);
-          };
+            // The "standard" macro name will be LIB<NAME>_{STATIC,SHARED},
+            // where <name> is the target name. Here we want to strike a
+            // balance between being unique and not too noisy.
+            //
+            string d ("-DLIB");
 
-          transform (t.name.begin (),
-                     t.name.end (),
-                     back_inserter (d),
-                     upcase_sanitize);
+            auto upcase_sanitize = [] (char c)
+            {
+              return (c == '-' || c == '+' || c == '.') ? '_' : ucase (c);
+            };
+
+            transform (t.name.begin (),
+                       t.name.end (),
+                       back_inserter (d),
+                       upcase_sanitize);
 
-          d += '_';
-          d += suffix;
+            d += '_';
+            d += suffix;
 
-          strings o;
-          o.push_back (move (d));
-          p.first.get () = move (o);
+            strings o;
+            o.push_back (move (d));
+            p.first.get () = move (o);
+          }
         }
       };
 
@@ -521,7 +517,7 @@ namespace build2
     match_result link::
     match (action a, target& t, const string& hint) const
     {
-      tracer trace ("cxx::link::match");
+      tracer trace (x, "link::match");
 
       // @@ TODO:
       //
@@ -537,16 +533,16 @@ namespace build2
 
       otype lt (link_type (t));
 
-      // Scan prerequisites and see if we can work with what we've got.
+      // Scan prerequisites and see if we can work with what we've got. Note
+      // that X could be C. We handle this by always checking for X first.
       //
-      bool seen_cxx (false), seen_c (false), seen_obj (false),
-        seen_lib (false);
+      bool seen_x (false), seen_c (false), seen_obj (false), seen_lib (false);
 
       for (prerequisite_member p: group_prerequisite_members (a, t))
       {
-        if (p.is_a<cxx> ())
+        if (p.is_a (x_src))
         {
-          seen_cxx = seen_cxx || true;
+          seen_x = seen_x || true;
         }
         else if (p.is_a<c> ())
         {
@@ -585,12 +581,12 @@ namespace build2
         }
       }
 
-      // We will only chain a C source if there is also a C++ source or we
-      // were explicitly told to.
+      // We will only chain a C source if there is also an X source or we were
+      // explicitly told to.
       //
-      if (seen_c && !seen_cxx && hint < "cxx")
+      if (seen_c && !seen_x && hint < x)
       {
-        l4 ([&]{trace << "C prerequisite(s) without C++ or hint";});
+        l4 ([&]{trace << "C prerequisite without " << x_lang << " or hint";});
         return nullptr;
       }
 
@@ -635,23 +631,19 @@ namespace build2
         }
       }
 
-      return seen_cxx || seen_c || seen_obj || seen_lib ? &t : nullptr;
+      return seen_x || seen_c || seen_obj || seen_lib ? &t : nullptr;
     }
 
     recipe link::
     apply (action a, target& xt, const match_result&) const
     {
-      tracer trace ("cxx::link::apply");
+      tracer trace (x, "link::apply");
 
       file& t (static_cast<file&> (xt));
 
       scope& bs (t.base_scope ());
       scope& rs (*bs.root_scope ());
 
-      const string& cid (cast<string> (rs["cxx.id"]));
-      const string& tsys (cast<string> (rs["cxx.target.system"]));
-      const string& tclass (cast<string> (rs["cxx.target.class"]));
-
       otype lt (link_type (t));
       lorder lo (link_order (bs, lt));
 
@@ -767,7 +759,8 @@ namespace build2
         //
         if (lt != otype::a &&
             cid == "msvc" &&
-            find_option ("/DEBUG", t, "cxx.loptions", true))
+            (find_option ("/DEBUG", t, c_loptions, true) ||
+             find_option ("/DEBUG", t, x_loptions, true)))
         {
           // Add after the import library if any.
           //
@@ -789,11 +782,11 @@ namespace build2
 
       optional<dir_paths> lib_paths; // Extract lazily.
 
-      // Process prerequisites: do rule chaining for C and C++ source
-      // files as well as search and match.
+      // Process prerequisites: do rule chaining for C and X source files as
+      // well as search and match.
       //
-      // When cleaning, ignore prerequisites that are not in the same
-      // or a subdirectory of our project root.
+      // When cleaning, ignore prerequisites that are not in the same or a
+      // subdirectory of our project root.
       //
       const target_type& ott (lt == otype::e ? obje::static_type :
                               lt == otype::a ? obja::static_type :
@@ -803,7 +796,7 @@ namespace build2
       {
         target* pt (nullptr);
 
-        if (!p.is_a<c> () && !p.is_a<cxx> ())
+        if (!p.is_a (x_src) && !p.is_a<c> ())
         {
           // Handle imported libraries.
           //
@@ -843,6 +836,9 @@ namespace build2
           continue;
         }
 
+        // The rest is rule chaining.
+        //
+
         // Which scope shall we use to resolve the root? Unlikely, but
         // possible, the prerequisite is from a different project
         // altogether. So we are going to use the target's project.
@@ -853,15 +849,15 @@ namespace build2
         //
         bool group (!p.prerequisite.belongs (t)); // Group's prerequisite.
 
-        const prerequisite_key& cp (p.key ()); // c(xx){} prerequisite key.
+        const prerequisite_key& cp (p.key ()); // C-source (X or C) key.
         const target_type& tt (group ? obj::static_type : ott);
 
-        // Come up with the obj*{} target. The c(xx){} prerequisite directory
+        // Come up with the obj*{} target. The source prerequisite directory
         // can be relative (to the scope) or absolute. If it is relative, then
         // use it as is. If absolute, then translate it to the corresponding
-        // directory under out_root. While the c(xx){} directory is most
-        // likely under src_root, it is also possible it is under out_root
-        // (e.g., generated source).
+        // directory under out_root. While the source directory is most likely
+        // under src_root, it is also possible it is under out_root (e.g.,
+        // generated source).
         //
         dir_path d;
         {
@@ -890,16 +886,16 @@ namespace build2
         //
         if (a.operation () == clean_id && !ot.dir.sub (rs.out_path ()))
         {
-          // If we shouldn't clean obj{}, then it is fair to assume
-          // we shouldn't clean cxx{} either (generated source will
-          // be in the same directory as obj{} and if not, well, go
-          // find yourself another build system ;-)).
+          // If we shouldn't clean obj{}, then it is fair to assume we
+          // shouldn't clean the source either (generated source will be in
+          // the same directory as obj{} and if not, well, go find yourself
+          // another build system ;-)).
           //
           continue; // Skip.
         }
 
-        // If we have created the obj{} target group, pick one of its
-        // members; the rest would be primarily concerned with it.
+        // If we have created the obj{} target group, pick one of its members;
+        // the rest would be primarily concerned with it.
         //
         if (group)
         {
@@ -933,43 +929,45 @@ namespace build2
         for (prerequisite_member p1:
                reverse_group_prerequisite_members (a, *pt))
         {
-          // Ignore some known target types (fsdir, headers, libraries).
+          // Most of the time we will have just a single source so fast-path
+          // that case.
           //
-          if (p1.is_a<fsdir> () ||
-              p1.is_a<h> ()     ||
-              (p.is_a<cxx> () && (p1.is_a<hxx> () ||
-                                  p1.is_a<ixx> () ||
-                                  p1.is_a<txx> ())) ||
-              p1.is_a<lib>  () ||
-              p1.is_a<liba> () ||
-              p1.is_a<libs> ())
+          if (p1.is_a (x_src))
           {
-            continue;
-          }
-
-          if (!p1.is_a<cxx> ())
-            fail << "synthesized target for prerequisite " << cp
-                 << " would be incompatible with existing target " << *pt <<
-              info << "unexpected existing prerequisite type " << p1 <<
-              info << "specify corresponding obj{} target explicitly";
+            if (!found)
+            {
+              build2::match (a, *pt); // Now p1 should be resolved.
 
-          if (!found)
-          {
-            build2::match (a, *pt); // Now p1 should be resolved.
+              // Searching our own prerequisite is ok.
+              //
+              if (&p.search () != &p1.search ())
+                fail << "synthesized target for prerequisite " << cp << " "
+                     << "would be incompatible with existing target " << *pt <<
+                  info << "existing prerequisite " << p1 << " does not match "
+                     << cp <<
+                  info << "specify corresponding " << tt.name << "{} target "
+                     << "explicitly";
+
+              found = true;
+            }
 
-            // Searching our own prerequisite is ok.
-            //
-            if (&p.search () != &p1.search ())
-              fail << "synthesized target for prerequisite " << cp << " would "
-                   << "be incompatible with existing target " << *pt <<
-                info << "existing prerequisite " << p1 << " does not match "
-                   << cp <<
-                info << "specify corresponding " << tt.name << "{} target "
-                   << "explicitly";
-
-            found = true;
-            // Check the rest of the prerequisites.
+            continue; // Check the rest of the prerequisites.
           }
+
+          // Ignore some known target types (fsdir, headers, libraries).
+          //
+          if (p1.is_a<fsdir> () ||
+              p1.is_a<lib>  ()  ||
+              p1.is_a<liba> ()  ||
+              p1.is_a<libs> ()  ||
+              (p.is_a (x_src) && x_header (p1)) ||
+              (p.is_a<c> () && p1.is_a<h> ()))
+            continue;
+
+          fail << "synthesized target for prerequisite " << cp
+               << " would be incompatible with existing target " << *pt <<
+            info << "unexpected existing prerequisite type " << p1 <<
+            info << "specify corresponding obj{} target explicitly";
         }
 
         if (!found)
@@ -978,12 +976,12 @@ namespace build2
           //
           ot.prerequisites.emplace_back (p.as_prerequisite (trace));
 
-          // Add our lib*{} prerequisites to the object file (see
-          // cxx.export.poptions above for details).
+          // Add our lib*{} prerequisites to the object file (see the export.*
+          // machinery for details).
           //
           // Note that we don't resolve lib{} to liba{}/libs{} here instead
           // leaving it to whoever (e.g., the compile rule) will be needing
-          // cxx.export.*. One reason for doing it there is that the object
+          // *.export.*. One reason for doing it there is that the object
           // target might be specified explicitly by the user in which case
           // they will have to specify the set of lib{} prerequisites and it's
           // much cleaner to do as lib{} rather than liba{}/libs{}.
@@ -1007,9 +1005,12 @@ namespace build2
 
       switch (a)
       {
-      case perform_update_id: return &perform_update;
-      case perform_clean_id: return &perform_clean;
-      default: return noop_recipe; // Configure update.
+      case perform_update_id:
+        return [this] (action a, target& t) {return perform_update (a, t);};
+      case perform_clean_id:
+        return [this] (action a, target& t) {return perform_clean (a, t);};
+      default:
+        return noop_recipe; // Configure update.
       }
     }
 
@@ -1059,47 +1060,38 @@ namespace build2
       }
     }
 
-    // See windows-manifest.cxx.
-    //
-    path
-    windows_manifest (file&, bool rpath_assembly);
-
     // See windows-rpath.cxx.
     //
     timestamp
     windows_rpath_timestamp (file&);
 
     void
-    windows_rpath_assembly (file&, timestamp, bool scratch);
-
-    const char*
-    msvc_machine (const string& cpu); // msvc.cxx
+    windows_rpath_assembly (file&, const string& cpu, timestamp, bool scratch);
 
     // Filter link.exe noise (msvc.cxx).
     //
     void
     msvc_filter_link (ifdstream&, const file&, otype);
 
+    // Translate target CPU to /MACHINE option.
+    //
+    const char*
+    msvc_machine (const string& cpu); // msvc.cxx
+
     target_state link::
-    perform_update (action a, target& xt)
+    perform_update (action a, target& xt) const
     {
-      tracer trace ("cxx::link::perform_update");
+      tracer trace (x, "link::perform_update");
 
       file& t (static_cast<file&> (xt));
 
+      scope& rs (t.root_scope ());
       otype lt (link_type (t));
 
       // Update prerequisites.
       //
       bool update (execute_prerequisites (a, t, t.mtime ()));
 
-      scope& rs (t.root_scope ());
-
-      const string& cid (cast<string> (rs["cxx.id"]));
-      const string& tgt (cast<string> (rs["cxx.target"]));
-      const string& tsys (cast<string> (rs["cxx.target.system"]));
-      const string& tclass (cast<string> (rs["cxx.target.class"]));
-
       // If targeting Windows, take care of the manifest.
       //
       path manifest; // Manifest itself (msvc) or compiled object file.
@@ -1213,12 +1205,12 @@ namespace build2
 
       // First should come the rule name/version.
       //
-      if (dd.expect ("cxx.link 1") != nullptr)
+      if (dd.expect (rule_id) != nullptr)
         l4 ([&]{trace << "rule mismatch forcing update of " << t;});
 
       lookup ranlib;
 
-      // Then the linker checksum (ar/ranlib or C++ compiler).
+      // Then the linker checksum (ar/ranlib or the compiler).
       //
       if (lt == otype::a)
       {
@@ -1244,16 +1236,16 @@ namespace build2
         //
         const string& cs (
           cast<string> (
-            rs[cid == "msvc" ? "bin.ld.checksum" : "cxx.checksum"]));
+            rs[cid == "msvc" ? var_pool["bin.ld.checksum"] : x_checksum]));
 
         if (dd.expect (cs) != nullptr)
           l4 ([&]{trace << "linker mismatch forcing update of " << t;});
       }
 
       // Next check the target. While it might be incorporated into the linker
-      // checksum, it also might not (e.g., MS link.exe).
+      // checksum, it also might not (e.g., VC link.exe).
       //
-      if (dd.expect (tgt) != nullptr)
+      if (dd.expect (ctg) != nullptr)
         l4 ([&]{trace << "target mismatch forcing update of " << t;});
 
       // Start building the command line. While we don't yet know whether we
@@ -1264,7 +1256,7 @@ namespace build2
       // second is simpler. Let's got with the simpler for now (actually it's
       // kind of a hybrid).
       //
-      cstrings args {nullptr}; // Reserve one for config.bin.ar/config.cxx.
+      cstrings args {nullptr}; // Reserve one for config.bin.ar/config.x.
 
       // Storage.
       //
@@ -1277,8 +1269,8 @@ namespace build2
         if (cid == "msvc") ;
         else
         {
-          // If the user asked for ranlib, don't try to do its function with -s.
-          // Some ar implementations (e.g., the LLVM one) doesn't support
+          // If the user asked for ranlib, don't try to do its function with
+          // -s.  Some ar implementations (e.g., the LLVM one) don't support
           // leading '-'.
           //
           args.push_back (ranlib ? "rc" : "rcs");
@@ -1288,16 +1280,18 @@ namespace build2
       {
         if (cid == "msvc")
         {
-          // We are using link.exe directly so we don't pass the C++ compiler
+          // We are using link.exe directly so don't pass the compiler
           // options.
         }
         else
         {
-          append_options (args, t, "cxx.coptions");
-          append_std (args, rs, cid, t, std);
+          append_options (args, t, c_coptions);
+          append_options (args, t, x_coptions);
+          append_std (args, rs, t, std);
         }
 
-        append_options (args, t, "cxx.loptions");
+        append_options (args, t, c_loptions);
+        append_options (args, t, x_loptions);
 
         // Handle soname/rpath.
         //
@@ -1309,7 +1303,7 @@ namespace build2
           auto l (t["bin.rpath"]);
 
           if (l && !l->empty ())
-            fail << tgt << " does not support rpath";
+            fail << ctg << " does not support rpath";
         }
         else
         {
@@ -1443,7 +1437,10 @@ namespace build2
         // Treat them as inputs, not options.
         //
         if (lt != otype::a)
-          hash_options (cs, t, "cxx.libs");
+        {
+          hash_options (cs, t, c_libs);
+          hash_options (cs, t, x_libs);
+        }
 
         if (dd.expect (cs.string ()) != nullptr)
           l4 ([&]{trace << "file set mismatch forcing update of " << t;});
@@ -1451,8 +1448,8 @@ namespace build2
 
       // If any of the above checks resulted in a mismatch (different linker,
       // options or input file set), or if the database is newer than the
-      // target (interrupted update) then force the target update. Also
-      // note this situation in the "from scratch" flag.
+      // target (interrupted update) then force the target update. Also note
+      // this situation in the "from scratch" flag.
       //
       bool scratch (false);
       if (dd.writing () || dd.mtime () > t.mtime ())
@@ -1484,14 +1481,13 @@ namespace build2
           {
             // lib.exe has /LIBPATH but it's not clear/documented what it's
             // used for. Perhaps for link-time code generation (/LTCG)? If
-            // that's the case, then we may need to pass cxx.loptions.
+            // that's the case, then we may need to pass *.loptions.
             //
             args.push_back ("/NOLOGO");
 
             // Add /MACHINE.
             //
-            args.push_back (
-              msvc_machine (cast<string> (rs["cxx.target.cpu"])));
+            args.push_back (msvc_machine (cast<string> (rs[x_target_cpu])));
 
             out = "/OUT:" + relt.string ();
             args.push_back (out.c_str ());
@@ -1518,8 +1514,7 @@ namespace build2
 
             // Add /MACHINE.
             //
-            args.push_back (
-              msvc_machine (cast<string> (rs["cxx.target.cpu"])));
+            args.push_back (msvc_machine (cast<string> (rs[x_target_cpu])));
 
             // Unless explicitly enabled with /INCREMENTAL, disable
             // incremental linking (it is implicitly enabled if /DEBUG is
@@ -1593,14 +1588,17 @@ namespace build2
 
             // @@ An executable can have an import library and VS seems to
             //    always name it. I wonder what would trigger its generation?
-            //    Could it be the presence of export symbols?
-
+            //    Could it be the presence of export symbols? Yes, link.exe
+            //    will generate the import library iff there are exported
+            //    symbols. Which means there could be a DLL without an import
+            //    library (which we currently don't handle very well).
+            //
             out = "/OUT:" + relt.string ();
             args.push_back (out.c_str ());
           }
           else
           {
-            args[0] = cast<path> (rs["config.cxx"]).string ().c_str ();
+            args[0] = cast<path> (rs[config_x]).string ().c_str ();
 
             // Add the option that triggers building a shared library and take
             // care of any extras (e.g., import library).
@@ -1676,7 +1674,10 @@ namespace build2
         args.push_back (sargs[i].c_str ());
 
       if (lt != otype::a)
-        append_options (args, t, "cxx.libs");
+      {
+        append_options (args, t, c_libs);
+        append_options (args, t, x_libs);
+      }
 
       args.push_back (nullptr);
 
@@ -1777,7 +1778,10 @@ namespace build2
       if (lt == otype::e && tclass == "windows")
       {
         if (a.outer_operation () != install_id)
-          windows_rpath_assembly (t, rpath_timestamp, scratch);
+          windows_rpath_assembly (t,
+                                  cast<string> (rs[x_target_cpu]),
+                                  rpath_timestamp,
+                                  scratch);
       }
 
       rm.cancel ();
@@ -1791,14 +1795,10 @@ namespace build2
     }
 
     target_state link::
-    perform_clean (action a, target& xt)
+    perform_clean (action a, target& xt) const
     {
       file& t (static_cast<file&> (xt));
 
-      scope& rs (t.root_scope ());
-      const string& tsys (cast<string> (rs["cxx.target.system"]));
-      const string& tclass (cast<string> (rs["cxx.target.class"]));
-
       initializer_list<const char*> e;
 
       switch (link_type (t))
@@ -1846,7 +1846,5 @@ namespace build2
 
       return clean_extra (a, t, e);
     }
-
-    link link::instance;
   }
 }
diff --git a/build2/cc/module b/build2/cc/module
new file mode 100644
index 0000000..bed7673
--- /dev/null
+++ b/build2/cc/module
@@ -0,0 +1,59 @@
+// file      : build2/cc/module -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_CC_MODULE
+#define BUILD2_CC_MODULE
+
+#include <build2/types>
+#include <build2/utility>
+
+#include <build2/module>
+#include <build2/variable>
+
+#include <build2/cc/common>
+
+#include <build2/cc/compile>
+#include <build2/cc/link>
+#include <build2/cc/install>
+
+namespace build2
+{
+  namespace cc
+  {
+    class config_module: public module_base, public virtual config_data
+    {
+    public:
+      explicit
+      config_module (config_data&& d) : config_data (move (d)) {}
+
+      void
+      init (scope&,
+            scope&,
+            const location&,
+            bool first,
+            const variable_map&);
+    };
+
+    class module: public module_base, protected virtual common,
+                  link, compile, install
+    {
+    public:
+      explicit
+      module (data&& d)
+          : common (move (d)),
+            link (move (d)),
+            compile (move (d), *this),
+            install (move (d), *this) {}
+
+      void
+      init (scope&,
+            scope&,
+            const location&,
+            bool first,
+            const variable_map&);
+    };
+  }
+}
+
+#endif // BUILD2_CC_MODULE
diff --git a/build2/cc/module.cxx b/build2/cc/module.cxx
new file mode 100644
index 0000000..3a7dad2
--- /dev/null
+++ b/build2/cc/module.cxx
@@ -0,0 +1,291 @@
+// file      : build2/cc/module.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <build2/cc/module>
+
+#include <iomanip> // left, setw()
+
+#include <butl/triplet>
+
+#include <build2/scope>
+#include <build2/context>
+#include <build2/diagnostics>
+
+#include <build2/bin/target>
+
+#include <build2/config/utility>
+#include <build2/install/utility>
+
+#include <build2/cc/guess>
+
+using namespace std;
+using namespace butl;
+
+namespace build2
+{
+  namespace cc
+  {
+    void config_module::
+    init (scope& r,
+          scope& b,
+          const location& loc,
+          bool first,
+          const variable_map&)
+    {
+      tracer trace (x, "config_init");
+
+      // Configure.
+      //
+      string pattern; // Toolchain pattern.
+
+      if (first)
+      {
+        const variable& config_c_coptions (var_pool["config.cc.coptions"]);
+
+        // config.x
+        //
+        auto p (config::required (r, config_x, path (x_default)));
+
+        // Figure out which compiler we are dealing with, its target, etc.
+        //
+        const path& xc (cast<path> (p.first));
+        compiler_info ci (
+          guess (x_lang,
+                 xc,
+                 cast_null<strings> (r[config_c_coptions]),
+                 cast_null<strings> (r[config_x_coptions])));
+
+        // If this is a new value (e.g., we are configuring), then print the
+        // report at verbosity level 2 and up (-v).
+        //
+        if (verb >= (p.second ? 2 : 3))
+        {
+          text << x << ' ' << project (r) << '@' << r.out_path () << '\n'
+               << "  " << left << setw (11) << x << xc << '\n'
+               << "  id         " << ci.id << '\n'
+               << "  version    " << ci.version.string << '\n'
+               << "  major      " << ci.version.major << '\n'
+               << "  minor      " << ci.version.minor << '\n'
+               << "  patch      " << ci.version.patch << '\n'
+               << "  build      " << ci.version.build << '\n'
+               << "  signature  " << ci.signature << '\n'
+               << "  checksum   " << ci.checksum << '\n'
+               << "  target     " << ci.target;
+        }
+
+        r.assign (x_id) = ci.id.string ();
+        r.assign (x_id_type) = move (ci.id.type);
+        r.assign (x_id_variant) = move (ci.id.variant);
+
+        r.assign (x_version) = move (ci.version.string);
+        r.assign (x_version_major) = ci.version.major;
+        r.assign (x_version_minor) = ci.version.minor;
+        r.assign (x_version_patch) = ci.version.patch;
+        r.assign (x_version_build) = move (ci.version.build);
+
+        r.assign (x_signature) = move (ci.signature);
+        r.assign (x_checksum) = move (ci.checksum);
+
+        pattern = move (ci.pattern);
+
+        // Split/canonicalize the target. First see if the user asked us to
+        // use config.sub.
+        //
+        if (ops.config_sub_specified ())
+        {
+          ci.target = run<string> (ops.config_sub (),
+                                   ci.target.c_str (),
+                                   [] (string& l) {return move (l);});
+          l5 ([&]{trace << "config.sub target: '" << ci.target << "'";});
+        }
+
+        try
+        {
+          string canon;
+          triplet t (ci.target, canon);
+
+          l5 ([&]{trace << "canonical target: '" << canon << "'; "
+                        << "class: " << t.class_;});
+
+          // Enter as x.target.{cpu,vendor,system,version,class}.
+          //
+          r.assign (x_target) = move (canon);
+          r.assign (x_target_cpu) = move (t.cpu);
+          r.assign (x_target_vendor) = move (t.vendor);
+          r.assign (x_target_system) = move (t.system);
+          r.assign (x_target_version) = move (t.version);
+          r.assign (x_target_class) = move (t.class_);
+        }
+        catch (const invalid_argument& e)
+        {
+          // This is where we suggest that the user specifies --config-sub to
+          // help us out.
+          //
+          fail << "unable to parse " << x_lang << "compiler target '"
+               << ci.target << "': " << e.what () <<
+            info << "consider using the --config-sub option";
+        }
+      }
+
+      // config.x.{p,c,l}options
+      // config.x.libs
+      //
+      // These are optional. We also merge them into the corresponding
+      // x.* variables.
+      //
+      // The merging part gets a bit tricky if this module has already
+      // been loaded in one of the outer scopes. By doing the straight
+      // append we would just be repeating the same options over and
+      // over. So what we are going to do is only append to a value if
+      // it came from this scope. Then the usage for merging becomes:
+      //
+      // x.coptions = <overridable options> # Note: '='.
+      // using x
+      // x.coptions += <overriding options> # Note: '+='.
+      //
+      b.assign (x_poptions) += cast_null<strings> (
+        config::optional (r, config_x_poptions));
+
+      b.assign (x_coptions) += cast_null<strings> (
+        config::optional (r, config_x_coptions));
+
+      b.assign (x_loptions) += cast_null<strings> (
+        config::optional (r, config_x_loptions));
+
+      b.assign (x_libs) += cast_null<strings> (
+        config::optional (r, config_x_libs));
+
+      // Load cc.config.
+      //
+      if (!cast_false<bool> (b["cc.config.loaded"]))
+      {
+        // Prepare configuration hints. They are only used on the first load
+        // of cc.config so we only populate them on our first load.
+        //
+        variable_map h;
+        if (first)
+        {
+          h.assign ("config.cc.id") = cast<string> (r[x_id]);
+          h.assign ("config.cc.target") = cast<string> (r[x_target]);
+          if (!pattern.empty ())
+            h.assign ("config.cc.pattern") = move (pattern);
+        }
+
+        load_module ("cc.config", r, b, loc, false, h);
+      }
+      else if (first)
+      {
+        // If cc.config is already loaded, verify its configuration matched
+        // ours since it could have been loaded by another c-family module.
+        //
+        auto check = [&r, &loc, this](const char* cv,
+                                      const variable& xv,
+                                      const char* w)
+        {
+          const string& c (cast<string> (r[cv]));
+          const string& x (cast<string> (r[xv]));
+
+          if (c != x)
+            fail (loc) << "cc and " << x << " module " << w << " mismatch" <<
+              info << cv << " is " << c <<
+              info << xv.name << " is " << x;
+        };
+
+        // Note that we don't require that patterns match. Presumably, if the
+        // toolchain id and target are the same, then where exactly the tools
+        // (e.g., ar) come from doesn't really matter.
+        //
+        check ("cc.id",     x_id,     "toolchain id");
+        check ("cc.target", x_target, "target");
+      }
+    }
+
+    void module::
+    init (scope& r,
+          scope& b,
+          const location& loc,
+          bool,
+          const variable_map&)
+    {
+      tracer trace (x, "init");
+
+      // Load cc.core. Besides other things, this will load bin (core) plus
+      // extra bin.* modules we may need.
+      //
+      if (!cast_false<bool> (b["cc.core.loaded"]))
+        load_module ("cc.core", r, b, loc);
+
+      // Register target types and configure their "installability".
+      //
+      {
+        using namespace install;
+
+        auto& t (b.target_types);
+
+        t.insert (x_src);
+
+        // Install headers into install.include.
+        //
+        for (const target_type* const* ht (x_hdr); *ht != nullptr; ++ht)
+        {
+          t.insert (**ht);
+          install_path (**ht, b, dir_path ("include"));
+        }
+      }
+
+      // Register rules.
+      //
+      {
+        using namespace bin;
+
+        auto& r (b.rules);
+
+        // We register for configure so that we detect unresolved imports
+        // during configuration rather that later, e.g., during update.
+        //
+        // @@ Should we check if install module was loaded (see bin)?
+        //
+        compile& cr (*this);
+        link&    lr (*this);
+        install& ir (*this);
+
+        r.insert<obje> (perform_update_id,   x_compile, cr);
+        r.insert<obje> (perform_clean_id,    x_compile, cr);
+        r.insert<obje> (configure_update_id, x_compile, cr);
+
+        r.insert<exe>  (perform_update_id,   x_link, lr);
+        r.insert<exe>  (perform_clean_id,    x_link, lr);
+        r.insert<exe>  (configure_update_id, x_link, lr);
+
+        r.insert<exe>  (perform_install_id,  x_install, ir);
+
+        // Only register static object/library rules if the bin.ar module is
+        // loaded (by us or by the user).
+        //
+        if (cast_false<bool> (b["bin.ar.loaded"]))
+        {
+          r.insert<obja> (perform_update_id,   x_compile, cr);
+          r.insert<obja> (perform_clean_id,    x_compile, cr);
+          r.insert<obja> (configure_update_id, x_compile, cr);
+
+          r.insert<liba> (perform_update_id,   x_link, lr);
+          r.insert<liba> (perform_clean_id,    x_link, lr);
+          r.insert<liba> (configure_update_id, x_link, lr);
+
+          r.insert<liba> (perform_install_id,  x_install, ir);
+        }
+
+        r.insert<objs> (perform_update_id,   x_compile, cr);
+        r.insert<objs> (perform_clean_id,    x_compile, cr);
+        r.insert<objs> (configure_update_id, x_compile, cr);
+
+        r.insert<libs> (perform_update_id,   x_link, lr);
+        r.insert<libs> (perform_clean_id,    x_link, lr);
+        r.insert<libs> (configure_update_id, x_link, lr);
+
+        r.insert<libs> (perform_install_id,  x_install, ir);
+      }
+    }
+  }
+}
diff --git a/build2/cxx/msvc.cxx b/build2/cc/msvc.cxx
index 9798046..84020d0 100644
--- a/build2/cxx/msvc.cxx
+++ b/build2/cc/msvc.cxx
@@ -1,4 +1,4 @@
-// file      : build2/cxx/msvc.cxx -*- C++ -*-
+// file      : build2/cc/msvc.cxx -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
@@ -11,14 +11,18 @@
 #include <build2/filesystem>
 #include <build2/diagnostics>
 
-#include <build2/cxx/common>
+#include <build2/bin/target>
+
+#include <build2/cc/types>
+
+#include <build2/cc/link>
 
 using namespace std;
 using namespace butl;
 
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
     using namespace bin;
 
@@ -82,8 +86,8 @@ namespace build2
 
     // Extract system library search paths from MSVC.
     //
-    void
-    msvc_library_search_paths (scope&, const string&, dir_paths&)
+    void link::
+    msvc_library_search_paths (scope&, dir_paths&) const
     {
       // The linker doesn't seem to have any built-in paths and all of them
       // come from the LIB environment variable.
@@ -212,16 +216,17 @@ namespace build2
 
     template <typename T>
     static T*
-    search_library (const path& ld,
-                    const dir_path& d,
-                    prerequisite& p,
-                    otype lt,
-                    const char* pfx,
-                    const char* sfx)
+    msvc_search_library (const char* mod,
+                         const path& ld,
+                         const dir_path& d,
+                         prerequisite& p,
+                         otype lt,
+                         const char* pfx,
+                         const char* sfx)
     {
       // Pretty similar logic to link::search_library().
       //
-      tracer trace ("cxx::msvc_search_library");
+      tracer trace (mod, "msvc_search_library");
 
       // Assemble the file path.
       //
@@ -269,14 +274,17 @@ namespace build2
       return nullptr;
     }
 
-    liba*
-    msvc_search_static (const path& ld, const dir_path& d, prerequisite& p)
+    liba* link::
+    msvc_search_static (const path& ld,
+                        const dir_path& d,
+                        prerequisite& p) const
     {
       liba* r (nullptr);
 
-      auto search = [&r, &ld, &d, &p] (const char* pf, const char* sf) -> bool
+      auto search = [&r, &ld, &d, &p, this] (const char* pf, const char* sf)
+        -> bool
       {
-        r = search_library<liba> (ld, d, p, otype::a, pf, sf);
+        r = msvc_search_library<liba> (x, ld, d, p, otype::a, pf, sf);
         return r != nullptr;
       };
 
@@ -293,17 +301,20 @@ namespace build2
         search ("",    "_static") ? r : nullptr;
     }
 
-    libs*
-    msvc_search_shared (const path& ld, const dir_path& d, prerequisite& p)
+    libs* link::
+    msvc_search_shared (const path& ld,
+                        const dir_path& d,
+                        prerequisite& p) const
     {
-      tracer trace ("cxx::msvc_search_shared");
+      tracer trace (x, "link::msvc_search_shared");
 
       libs* r (nullptr);
 
-      auto search = [&r, &ld, &d, &p, &trace] (
+      auto search = [&r, &ld, &d, &p, &trace, this] (
         const char* pf, const char* sf) -> bool
       {
-        if (libi* i = search_library<libi> (ld, d, p, otype::s, pf, sf))
+        if (libi* i =
+              msvc_search_library<libi> (x, ld, d, p, otype::s, pf, sf))
         {
           r = &targets.insert<libs> (d, dir_path (), p.name, nullptr, trace);
 
diff --git a/build2/cc/target b/build2/cc/target
new file mode 100644
index 0000000..2d8125b
--- /dev/null
+++ b/build2/cc/target
@@ -0,0 +1,48 @@
+// file      : build2/cc/target -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_CC_TARGET
+#define BUILD2_CC_TARGET
+
+#include <build2/types>
+#include <build2/utility>
+
+#include <build2/target>
+
+namespace build2
+{
+  namespace cc
+  {
+    // There is hardly a c-family compilation without a C header inclusion.
+    // As a result, this target type is registered for any c-family module.
+    //
+    class h: public file
+    {
+    public:
+      using file::file;
+
+    public:
+      static const target_type static_type;
+      virtual const target_type& dynamic_type () const {return static_type;}
+    };
+
+    // This one we define in cc but the target type is only registered by the
+    // c module. This way we can implement rule chaining without jumping
+    // through too many hoops (like resolving target type dynamically) but
+    // also without relaxing things too much (i.e., the user still won't be
+    // able to refer to c{} without loading the c module).
+    //
+    class c: public file
+    {
+    public:
+      using file::file;
+
+    public:
+      static const target_type static_type;
+      virtual const target_type& dynamic_type () const {return static_type;}
+    };
+  }
+}
+
+#endif // BUILD2_CC_TARGET
diff --git a/build2/cc/target.cxx b/build2/cc/target.cxx
new file mode 100644
index 0000000..7c2bb24
--- /dev/null
+++ b/build2/cc/target.cxx
@@ -0,0 +1,39 @@
+// file      : build2/cc/target.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <build2/cc/target>
+
+using namespace std;
+
+namespace build2
+{
+  namespace cc
+  {
+    extern const char ext_var[] = "extension";  // VC 19 rejects constexpr.
+
+    extern const char h_ext_def[] = "h";
+    const target_type h::static_type
+    {
+      "h",
+      &file::static_type,
+      &target_factory<h>,
+      &target_extension_var<ext_var, h_ext_def>,
+      nullptr,
+      &search_file,
+      false
+    };
+
+    extern const char c_ext_def[] = "c";
+    const target_type c::static_type
+    {
+      "c",
+      &file::static_type,
+      &target_factory<c>,
+      &target_extension_var<ext_var, c_ext_def>,
+      nullptr,
+      &search_file,
+      false
+    };
+  }
+}
diff --git a/build2/cc/types b/build2/cc/types
new file mode 100644
index 0000000..9cacc60
--- /dev/null
+++ b/build2/cc/types
@@ -0,0 +1,32 @@
+// file      : build2/cc/types -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_CC_TYPES
+#define BUILD2_CC_TYPES
+
+#include <build2/types>
+#include <build2/utility>
+
+namespace build2
+{
+  namespace cc
+  {
+    // Compiler language.
+    //
+    enum class lang {c, cxx};
+
+    ostream&
+    operator<< (ostream&, lang); // utility.ixx
+
+    // Compile/link output type (executable, static, or shared).
+    //
+    enum class otype {e, a, s};
+
+    // Library link order.
+    //
+    enum class lorder {a, s, a_s, s_a};
+  }
+}
+
+#endif // BUILD2_CC_TYPES
diff --git a/build2/cxx/common b/build2/cc/utility
index 77f1149..ae19d56 100644
--- a/build2/cxx/common
+++ b/build2/cc/utility
@@ -1,45 +1,34 @@
-// file      : build2/cxx/common -*- C++ -*-
+// file      : build2/cc/utility -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#ifndef BUILD2_CXX_COMMON
-#define BUILD2_CXX_COMMON
+#ifndef BUILD2_CC_UTILITY
+#define BUILD2_CC_UTILITY
 
 #include <build2/types>
 #include <build2/utility>
 
+#include <build2/target>
 #include <build2/bin/target>
 
+#include <build2/cc/types>
+
 namespace build2
 {
-  namespace cxx
+  struct variable;
+
+  namespace cc
   {
-    // Compile/link output type (executable, static, or shared).
+    // Compile/link output type.
     //
-    enum class otype {e, a, s};
-
-    inline otype
-    compile_type (target& t)
-    {
-      return
-        t.is_a<bin::obje> () ? otype::e :
-        t.is_a<bin::obja> () ? otype::a :
-        otype::s;
-    }
-
-    inline otype
-    link_type (target& t)
-    {
-      return
-        t.is_a<bin::exe> ()  ? otype::e :
-        t.is_a<bin::liba> () ? otype::a :
-        otype::s;
-    }
+    otype
+    compile_type (target&);
+
+    otype
+    link_type (target&);
 
     // Library link order.
     //
-    enum class lorder {a, s, a_s, s_a};
-
     // The reason we pass scope and not the target is because this function is
     // called not only for exe/lib but also for obj as part of the library
     // meta-information protocol implementation. Normally the bin.*.lib values
@@ -54,7 +43,22 @@ namespace build2
     //
     target&
     link_member (bin::lib&, lorder);
+
+    // Append or hash library options from a pair of *.export.* variables
+    // (first one is cc.export.*) recursively, prerequisite libraries first.
+    //
+    void
+    append_lib_options (cstrings&, target&, lorder,
+                        const variable&,
+                        const variable&);
+
+    void
+    hash_lib_options (sha256&, target&, lorder,
+                      const variable&,
+                      const variable&);
   }
 }
 
-#endif // BUILD2_CXX_COMMON
+#include <build2/cc/utility.ixx>
+
+#endif // BUILD2_CC_UTILITY
diff --git a/build2/cxx/common.cxx b/build2/cc/utility.cxx
index ec724a5..773ba8f 100644
--- a/build2/cxx/common.cxx
+++ b/build2/cc/utility.cxx
@@ -1,25 +1,27 @@
-// file      : build2/cxx/common.cxx -*- C++ -*-
+// file      : build2/cc/utility.cxx -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#include <build2/cxx/common>
+#include <build2/cc/utility>
 
 #include <build2/variable>
-#include <build2/algorithm>
+#include <build2/algorithm> // search()
+
+#include <build2/bin/target>
 
 using namespace std;
 
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
     using namespace bin;
 
     lorder
     link_order (scope& bs, otype ot)
     {
-      // Initialize to suppress 'may be used uninitialized' warning produced by
-      // MinGW GCC 5.4.0.
+      // Initialize to suppress 'may be used uninitialized' warning produced
+      // by MinGW GCC 5.4.0.
       //
       const char* var (nullptr);
 
@@ -69,5 +71,45 @@ namespace build2
 
       return *r;
     }
+
+    void
+    append_lib_options (cstrings& args, target& l, lorder lo,
+                        const variable& cv,
+                        const variable& xv)
+    {
+      using namespace bin;
+
+      for (target* t: l.prerequisite_targets)
+      {
+        if (lib* l = t->is_a<lib> ())
+          t = &link_member (*l, lo); // Pick one of the members.
+
+        if (t->is_a<liba> () || t->is_a<libs> ())
+          append_lib_options (args, *t, lo, cv, xv);
+      }
+
+      append_options (args, l, cv);
+      append_options (args, l, xv);
+    }
+
+    void
+    hash_lib_options (sha256& csum, target& l, lorder lo,
+                      const variable& cv,
+                      const variable& xv)
+    {
+      using namespace bin;
+
+      for (target* t: l.prerequisite_targets)
+      {
+        if (lib* l = t->is_a<lib> ())
+          t = &link_member (*l, lo); // Pick one of the members.
+
+        if (t->is_a<liba> () || t->is_a<libs> ())
+          hash_lib_options (csum, *t, lo, cv, xv);
+      }
+
+      hash_options (csum, l, cv);
+      hash_options (csum, l, xv);
+    }
   }
 }
diff --git a/build2/cc/utility.ixx b/build2/cc/utility.ixx
new file mode 100644
index 0000000..e7eb565
--- /dev/null
+++ b/build2/cc/utility.ixx
@@ -0,0 +1,33 @@
+// file      : build2/cc/utility.ixx -*- C++ -*-
+// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+namespace build2
+{
+  namespace cc
+  {
+    inline ostream&
+    operator<< (ostream& os, lang l)
+    {
+      return os << (l == lang::c ? "C" : "C++");
+    }
+
+    inline otype
+    compile_type (target& t)
+    {
+      return
+        t.is_a<bin::obje> () ? otype::e :
+        t.is_a<bin::obja> () ? otype::a :
+        otype::s;
+    }
+
+    inline otype
+    link_type (target& t)
+    {
+      return
+        t.is_a<bin::exe> ()  ? otype::e :
+        t.is_a<bin::liba> () ? otype::a :
+        otype::s;
+    }
+  }
+}
diff --git a/build2/cxx/windows-manifest.cxx b/build2/cc/windows-manifest.cxx
index 915610d..0666ef5 100644
--- a/build2/cxx/windows-manifest.cxx
+++ b/build2/cc/windows-manifest.cxx
@@ -1,4 +1,4 @@
-// file      : build2/cxx/windows-manifest.cxx -*- C++ -*-
+// file      : build2/cc/windows-manifest.cxx -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
@@ -9,12 +9,14 @@
 #include <build2/filesystem>
 #include <build2/diagnostics>
 
+#include <build2/cc/link>
+
 using namespace std;
 using namespace butl;
 
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
     // Translate the compiler target CPU value to the processorArchitecture
     // attribute value.
@@ -36,16 +38,14 @@ namespace build2
     // Generate a Windows manifest and if necessary create/update the manifest
     // file corresponding to the exe{} target. Return the manifest file path.
     //
-    path
-    windows_manifest (file& t, bool rpath_assembly)
+    path link::
+    windows_manifest (file& t, bool rpath_assembly) const
     {
-      tracer trace ("cxx::windows_manifest");
+      tracer trace (x, "windows_manifest");
 
       scope& rs (t.root_scope ());
 
-      const char* pa (
-        windows_manifest_arch (
-          cast<string> (rs["cxx.target.cpu"])));
+      const char* pa (windows_manifest_arch (cast<string> (rs[x_target_cpu])));
 
       string m;
 
diff --git a/build2/cxx/windows-rpath.cxx b/build2/cc/windows-rpath.cxx
index b52315c..ea20a5c 100644
--- a/build2/cxx/windows-rpath.cxx
+++ b/build2/cc/windows-rpath.cxx
@@ -1,4 +1,4 @@
-// file      : build2/cxx/windows-rpath.cxx -*- C++ -*-
+// file      : build2/cc/windows-rpath.cxx -*- C++ -*-
 // copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
@@ -19,7 +19,7 @@ using namespace butl;
 
 namespace build2
 {
-  namespace cxx
+  namespace cc
   {
     // Provide limited emulation of the rpath functionality on Windows using a
     // side-by-side assembly. In a nutshell, the idea is to create an assembly
@@ -104,7 +104,10 @@ namespace build2
     // manifest file.
     //
     void
-    windows_rpath_assembly (file& t, timestamp ts, bool scratch)
+    windows_rpath_assembly (file& t,
+                            const string& tcpu,
+                            timestamp ts,
+                            bool scratch)
     {
       // Assembly paths and name.
       //
@@ -129,8 +132,6 @@ namespace build2
           return;
       }
 
-      scope& rs (t.root_scope ());
-
       // Next collect the set of DLLs that will be in our assembly. We need to
       // do this recursively which means we may end up with duplicates. Also,
       // it is possible that there aren't/no longer are any DLLs which means
@@ -157,9 +158,7 @@ namespace build2
           mkdir (ad, 3);
       }
 
-      const char* pa (
-        windows_manifest_arch (
-          cast<string> (rs["cxx.target.cpu"])));
+      const char* pa (windows_manifest_arch (tcpu));
 
       if (verb >= 3)
         text << "cat >" << am;
@@ -176,7 +175,7 @@ namespace build2
             << "                    processorArchitecture='" << pa << "'\n"
             << "                    version='0.0.0.0'/>\n";
 
-        scope& as (*rs.weak_scope ()); // Amalgamation scope.
+        scope& as (*t.root_scope ().weak_scope ()); // Amalgamation scope.
 
         auto link = [&as, &ad] (const path& f, const path& l)
         {
diff --git a/build2/cxx/compile b/build2/cxx/compile
deleted file mode 100644
index 16c62e6..0000000
--- a/build2/cxx/compile
+++ /dev/null
@@ -1,37 +0,0 @@
-// file      : build2/cxx/compile -*- C++ -*-
-// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#ifndef BUILD2_CXX_COMPILE
-#define BUILD2_CXX_COMPILE
-
-#include <build2/types>
-#include <build2/utility>
-
-#include <build2/rule>
-
-namespace build2
-{
-  namespace cxx
-  {
-    class compile: public rule
-    {
-    public:
-      virtual match_result
-      match (action, target&, const string& hint) const;
-
-      virtual recipe
-      apply (action, target&, const match_result&) const;
-
-      static target_state
-      perform_update (action, target&);
-
-      static target_state
-      perform_clean (action, target&);
-
-      static compile instance;
-    };
-  }
-}
-
-#endif // BUILD2_CXX_COMPILE
diff --git a/build2/cxx/link b/build2/cxx/link
deleted file mode 100644
index 4f00ea0..0000000
--- a/build2/cxx/link
+++ /dev/null
@@ -1,48 +0,0 @@
-// file      : build2/cxx/link -*- C++ -*-
-// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#ifndef BUILD2_CXX_LINK
-#define BUILD2_CXX_LINK
-
-#include <build2/types>
-#include <build2/utility>
-
-#include <build2/rule>
-
-#include <build2/bin/target>
-
-namespace build2
-{
-  namespace cxx
-  {
-    class link: public rule
-    {
-    public:
-      virtual match_result
-      match (action, target&, const string& hint) const;
-
-      virtual recipe
-      apply (action, target&, const match_result&) const;
-
-      static target_state
-      perform_update (action, target&);
-
-      static target_state
-      perform_clean (action, target&);
-
-      static link instance;
-
-    private:
-      friend class compile;
-
-      static target*
-      search_library (optional<dir_paths>&, prerequisite&);
-
-      static dir_paths
-      extract_library_paths (scope&);
-    };
-  }
-}
-
-#endif // BUILD2_CXX_LINK
diff --git a/build2/cxx/module b/build2/cxx/module
index 37466ef..8c1a01f 100644
--- a/build2/cxx/module
+++ b/build2/cxx/module
@@ -15,6 +15,15 @@ namespace build2
   namespace cxx
   {
     bool
+    config_init (scope&,
+                 scope&,
+                 const location&,
+                 unique_ptr<module_base>&,
+                 bool,
+                 bool,
+                 const variable_map&);
+
+    bool
     init (scope&,
           scope&,
           const location&,
diff --git a/build2/cxx/module.cxx b/build2/cxx/module.cxx
index f66ef53..fd98114 100644
--- a/build2/cxx/module.cxx
+++ b/build2/cxx/module.cxx
@@ -4,23 +4,13 @@
 
 #include <build2/cxx/module>
 
-#include <butl/triplet>
-
 #include <build2/scope>
 #include <build2/context>
 #include <build2/diagnostics>
 
-#include <build2/config/utility>
-#include <build2/install/utility>
-
-#include <build2/bin/target>
+#include <build2/cc/module>
 
-#include <build2/cxx/link>
-#include <build2/cxx/guess>
 #include <build2/cxx/target>
-#include <build2/cxx/compile>
-#include <build2/cxx/install>
-#include <build2/cxx/utility>
 
 using namespace std;
 using namespace butl;
@@ -29,355 +19,228 @@ namespace build2
 {
   namespace cxx
   {
-    bool
-    init (scope& r,
-          scope& b,
-          const location& loc,
-          unique_ptr<module_base>&,
-          bool first,
-          bool,
-          const variable_map& config_hints)
-    {
-      tracer trace ("cxx::init");
-      l5 ([&]{trace << "for " << b.out_path ();});
-
-      // Enter module variables.
-      //
-      if (first)
-      {
-        auto& v (var_pool);
+    using cc::config_module;
 
-        // Note: some overridable, some not.
-        //
-        v.insert<path>    ("config.cxx",          true);
-        v.insert<strings> ("config.cxx.poptions", true);
-        v.insert<strings> ("config.cxx.coptions", true);
-        v.insert<strings> ("config.cxx.loptions", true);
-        v.insert<strings> ("config.cxx.libs",     true);
-
-        v.insert<strings> ("cxx.poptions");
-        v.insert<strings> ("cxx.coptions");
-        v.insert<strings> ("cxx.loptions");
-        v.insert<strings> ("cxx.libs");
-
-        v.insert<strings> ("cxx.export.poptions");
-        v.insert<strings> ("cxx.export.coptions");
-        v.insert<strings> ("cxx.export.loptions");
-        v.insert<strings> ("cxx.export.libs");
-
-        v.insert<string> ("cxx.std",              true);
-      }
-
-      // Configure.
-      //
-
-      assert (config_hints.empty ()); // We don't known any hints.
-
-      // config.cxx.{p,c,l}options
-      // config.cxx.libs
-      //
-      // These are optional. We also merge them into the corresponding
-      // cxx.* variables.
-      //
-      // The merging part gets a bit tricky if this module has already
-      // been loaded in one of the outer scopes. By doing the straight
-      // append we would just be repeating the same options over and
-      // over. So what we are going to do is only append to a value if
-      // it came from this scope. Then the usage for merging becomes:
-      //
-      // cxx.coptions = <overridable options> # Note: '='.
-      // using cxx
-      // cxx.coptions += <overriding options> # Note: '+='.
-      //
-      b.assign ("cxx.poptions") += cast_null<strings> (
-        config::optional (r, "config.cxx.poptions"));
-
-      b.assign ("cxx.coptions") += cast_null<strings> (
-        config::optional (r, "config.cxx.coptions"));
-
-      b.assign ("cxx.loptions") += cast_null<strings> (
-        config::optional (r, "config.cxx.loptions"));
+    class module: public cc::module
+    {
+    public:
+      explicit
+      module (data&& d): common (move (d)), cc::module (move (d)) {}
 
-      b.assign ("cxx.libs") += cast_null<strings> (
-        config::optional (r, "config.cxx.libs"));
+      bool
+      translate_std (string&, scope&, const value&) const override;
+    };
 
-      // Configuration hints for the bin module. They will only be used on the
-      // first loading of the bin module (for this project) so we only
-      // populate them on our first loading.
-      //
-      variable_map bin_hints;
+    bool module::
+    translate_std (string& s, scope& r, const value& val) const
+    {
+      const string& v (cast<string> (val));
 
-      // config.cxx
-      //
-      if (first)
+      if (cid == "msvc")
       {
-        auto p (config::required (r, "config.cxx", path ("g++")));
-
-        // Figure out which compiler we are dealing with, its target, etc.
+        // C++ standard-wise, with VC you get what you get. The question is
+        // whether we should verify that the requested standard is provided by
+        // this VC version. And if so, from which version should we say VC
+        // supports 11, 14, and 17? We should probably be as loose as possible
+        // here since the author will always be able to tighten (but not
+        // loosen) this in the buildfile (i.e., detect unsupported versions).
         //
-        const path& cxx (cast<path> (p.first));
-        compiler_info ci (guess (cxx, cast_null<strings> (r["cxx.coptions"])));
-
-        // If this is a new value (e.g., we are configuring), then print the
-        // report at verbosity level 2 and up (-v).
+        // For now we are not going to bother doing this for C++03.
         //
-        if (verb >= (p.second ? 2 : 3))
+        if (v != "98" && v != "03")
         {
-          text << "cxx " << project (r) << '@' << r.out_path () << '\n'
-               << "  cxx        " << cxx << '\n'
-               << "  id         " << ci.id << '\n'
-               << "  version    " << ci.version.string << '\n'
-               << "  major      " << ci.version.major << '\n'
-               << "  minor      " << ci.version.minor << '\n'
-               << "  patch      " << ci.version.patch << '\n'
-               << "  build      " << ci.version.build << '\n'
-               << "  signature  " << ci.signature << '\n'
-               << "  checksum   " << ci.checksum << '\n'
-               << "  target     " << ci.target;
-        }
-
-        r.assign<string> ("cxx.id") = ci.id.string ();
-        r.assign<string> ("cxx.id.type") = move (ci.id.type);
-        r.assign<string> ("cxx.id.variant") = move (ci.id.variant);
-
-        r.assign<string> ("cxx.version") = move (ci.version.string);
-        r.assign<uint64_t> ("cxx.version.major") = ci.version.major;
-        r.assign<uint64_t> ("cxx.version.minor") = ci.version.minor;
-        r.assign<uint64_t> ("cxx.version.patch") = ci.version.patch;
-        r.assign<string> ("cxx.version.build") = move (ci.version.build);
+          uint64_t cver (cast<uint64_t> (r[x_version_major]));
 
-        r.assign<string> ("cxx.signature") = move (ci.signature);
-        r.assign<string> ("cxx.checksum") = move (ci.checksum);
-
-        // While we still have the original, compiler-reported target, see if
-        // we can derive a binutils program pattern.
-        //
-        // BTW, for GCC we also get gcc-{ar,ranlib} which add support for the
-        // LTO plugin though it seems more recent GNU binutils (2.25) are able
-        // to load the plugin when needed automatically. So it doesn't seem we
-        // should bother trying to support this on our end (the way we could
-        // do it is by passing config.bin.{ar,ranlib} as hints).
-        //
-        string pattern;
-
-        if (cast<string> (r["cxx.id"]) == "msvc")
-        {
-          // If the compiler name is/starts with 'cl' (e.g., cl.exe, cl-14),
-          // then replace it with '*' and use it as a pattern for lib, link,
-          // etc.
+          // @@ Is mapping for 14 and 17 correct? Maybe Update 2 for 14?
           //
-          if (cxx.size () > 2)
+          if ((v == "11" && cver < 16) || // C++11 since VS2010/10.0.
+              (v == "14" && cver < 19) || // C++14 since VS2015/14.0.
+              (v == "17" && cver < 20))   // C++17 since VS20??/15.0.
           {
-            const string& l (cxx.leaf ().string ());
-            size_t n (l.size ());
-
-            if (n >= 2 &&
-                (l[0] == 'c' || l[0] == 'C') &&
-                (l[1] == 'l' || l[1] == 'L') &&
-                (n == 2 || l[2] == '.' || l[2] == '-'))
-            {
-              path p (cxx.directory ());
-              p /= "*";
-              p += l.c_str () + 2;
-              pattern = move (p).string ();
-            }
+            fail << "C++" << v << " is not supported by "
+                 << cast<string> (r[x_signature]) <<
+              info << "required by " << project (r) << '@' << r.out_path ();
           }
         }
+
+        return false;
+      }
+      else
+      {
+        // Translate 11 to 0x, 14 to 1y, and 17 to 1z for compatibility with
+        // older versions of the compilers.
+        //
+        s = "-std=";
+
+        if (v == "98")
+          s += "c++98";
+        else if (v == "03")
+          s += "c++03";
+        else if (v == "11")
+          s += "c++0x";
+        else if (v == "14")
+          s += "c++1y";
+        else if (v == "17")
+          s += "c++1z";
         else
-        {
-          // When cross-compiling the whole toolchain is normally prefixed
-          // with the target triplet, e.g., x86_64-w64-mingw32-{g++,ar,ld}.
-          //
-          const string& t (ci.target);
-          size_t n (t.size ());
+          s += v; // In case the user specifies something like 'gnu++17'.
 
-          if (cxx.size () > n + 1)
-          {
-            const string& l (cxx.leaf ().string ());
-
-            if (l.size () > n + 1 && l.compare (0, n, t) == 0 && l[n] == '-')
-            {
-              path p (cxx.directory ());
-              p /= t;
-              p += "-*";
-              pattern = move (p).string ();
-            }
-          }
-        }
+        return true;
+      }
+    }
 
-        if (!pattern.empty ())
-          bin_hints.assign ("config.bin.pattern") = move (pattern);
+    bool
+    config_init (scope& r,
+                 scope& b,
+                 const location& loc,
+                 unique_ptr<module_base>& m,
+                 bool first,
+                 bool,
+                 const variable_map& hints)
+    {
+      tracer trace ("cxx::config_init");
+      l5 ([&]{trace << "for " << b.out_path ();});
 
-        // Split/canonicalize the target.
+      if (first)
+      {
+        // Load cc.vars so that we can cache all the cc.* variables.
         //
+        if (!cast_false<bool> (b["cc.vars.loaded"]))
+          load_module ("cc.vars", r, b, loc);
 
-        // Did the user ask us to use config.sub?
+        // Enter all the variables and initialize the module data.
         //
-        if (ops.config_sub_specified ())
-        {
-          ci.target = run<string> (ops.config_sub (),
-                                   ci.target.c_str (),
-                                   [] (string& l) {return move (l);});
-          l5 ([&]{trace << "config.sub target: '" << ci.target << "'";});
-        }
-
-        try
-        {
-          string canon;
-          triplet t (ci.target, canon);
+        auto& v (var_pool);
 
-          l5 ([&]{trace << "canonical target: '" << canon << "'; "
-                        << "class: " << t.class_;});
+        cc::config_data d {
+          cc::lang::cxx,
 
-          // Pass the target we extracted from the C++ compiler as a config
-          // hint to the bin module.
-          //
-          bin_hints.assign ("config.bin.target") = canon;
+          "cxx",
+          "c++",
+          "g++",
 
-          // Enter as cxx.target.{cpu,vendor,system,version,class}.
+          // Note: some overridable, some not.
           //
-          r.assign<string> ("cxx.target") = move (canon);
-          r.assign<string> ("cxx.target.cpu") = move (t.cpu);
-          r.assign<string> ("cxx.target.vendor") = move (t.vendor);
-          r.assign<string> ("cxx.target.system") = move (t.system);
-          r.assign<string> ("cxx.target.version") = move (t.version);
-          r.assign<string> ("cxx.target.class") = move (t.class_);
-        }
-        catch (const invalid_argument& e)
-        {
-          // This is where we suggest that the user specifies --config-sub to
-          // help us out.
-          //
-          fail << "unable to parse compiler target '" << ci.target << "': "
-               << e.what () <<
-            info << "consider using the --config-sub option";
-        }
-      }
-
-      const string& cid (cast<string> (r["cxx.id"]));
-      const string& tsys (cast<string> (r["cxx.target.system"]));
-
-      // Initialize the bin module. Only do this if it hasn't already been
-      // loaded so that we don't overwrite user's bin.* settings.
-      //
-      if (!cast_false<bool> (b["bin.loaded"]))
-        load_module ("bin", r, b, loc, false, bin_hints);
-
-      // Verify bin's target matches ours.
-      //
-      {
-        const string& bt (cast<string> (r["bin.target"]));
-        const string& ct (cast<string> (r["cxx.target"]));
-
-        if (bt != ct)
-          fail (loc) << "bin and cxx module target platform mismatch" <<
-            info << "bin.target is " << bt <<
-            info << "cxx.target is " << ct;
+          v.insert<path>     ("config.cxx",          true),
+          v.insert<strings>  ("config.cxx.poptions", true),
+          v.insert<strings>  ("config.cxx.coptions", true),
+          v.insert<strings>  ("config.cxx.loptions", true),
+          v.insert<strings>  ("config.cxx.libs",     true),
+
+          v.insert<strings>  ("cxx.poptions"),
+          v.insert<strings>  ("cxx.coptions"),
+          v.insert<strings>  ("cxx.loptions"),
+          v.insert<strings>  ("cxx.libs"),
+
+          v["cc.poptions"],
+          v["cc.coptions"],
+          v["cc.loptions"],
+          v["cc.libs"],
+
+          v.insert<strings>  ("cxx.export.poptions"),
+          v.insert<strings>  ("cxx.export.coptions"),
+          v.insert<strings>  ("cxx.export.loptions"),
+          v.insert<strings>  ("cxx.export.libs"),
+
+          v["cc.export.poptions"],
+          v["cc.export.coptions"],
+          v["cc.export.loptions"],
+          v["cc.export.libs"],
+
+          v.insert<string>   ("cxx.std", true),
+
+          v.insert<string>   ("cxx.id"),
+          v.insert<string>   ("cxx.id.type"),
+          v.insert<string>   ("cxx.id.variant"),
+
+          v.insert<string>   ("cxx.version"),
+          v.insert<uint64_t> ("cxx.version.major"),
+          v.insert<uint64_t> ("cxx.version.minor"),
+          v.insert<uint64_t> ("cxx.version.patch"),
+          v.insert<string>   ("cxx.version.build"),
+
+          v.insert<string>   ("cxx.signature"),
+          v.insert<string>   ("cxx.checksum"),
+
+          v.insert<string>   ("cxx.target"),
+          v.insert<string>   ("cxx.target.cpu"),
+          v.insert<string>   ("cxx.target.vendor"),
+          v.insert<string>   ("cxx.target.system"),
+          v.insert<string>   ("cxx.target.version"),
+          v.insert<string>   ("cxx.target.class")
+        };
+
+        assert (m == nullptr);
+        m.reset (new config_module (move (d)));
       }
 
-      // Load the bin.ar module unless we were asked to only build shared
-      // libraries.
-      //
-      if (auto l = r["config.bin.lib"])
-      {
-        if (cast<string> (l) != "shared")
-        {
-          if (!cast_false<bool> (b["bin.ar.loaded"]))
-            load_module ("bin.ar", r, b, loc, false, bin_hints);
-        }
-      }
+      static_cast<config_module&> (*m).init (r, b, loc, first, hints);
+      return true;
+    }
 
-      // In the VC world you link things directly with link.exe so load the
-      // bin.ld module.
-      //
-      if (cid == "msvc")
-      {
-        if (!cast_false<bool> (b["bin.ld.loaded"]))
-          load_module ("bin.ld", r, b, loc, false, bin_hints);
-      }
+    static const target_type* hdr[] =
+    {
+      &hxx::static_type,
+      &ixx::static_type,
+      &txx::static_type,
+      &h::static_type,
+      nullptr
+    };
+
+    static const target_type* inc[] =
+    {
+      &hxx::static_type,
+      &ixx::static_type,
+      &txx::static_type,
+      &cxx::static_type,
+      &h::static_type,
+      &c::static_type,
+      nullptr
+    };
 
-      // If our target is MinGW, then we will need the resource compiler
-      // (windres) in order to embed the manifest.
-      //
-      if (tsys == "mingw32")
-      {
-        if (!cast_false<bool> (b["bin.rc.loaded"]))
-          load_module ("bin.rc", r, b, loc, false, bin_hints);
-      }
+    bool
+    init (scope& r,
+          scope& b,
+          const location& loc,
+          unique_ptr<module_base>& m,
+          bool first,
+          bool,
+          const variable_map& hints)
+    {
+      tracer trace ("cxx::init");
+      l5 ([&]{trace << "for " << b.out_path ();});
 
-      // Register target types.
+      // Load cxx.config.
       //
-      {
-        auto& t (b.target_types);
-
-        t.insert<h> ();
-        t.insert<c> ();
+      if (!cast_false<bool> (b["cxx.config.loaded"]))
+        load_module ("cxx.config", r, b, loc, false, hints);
 
-        t.insert<cxx> ();
-        t.insert<hxx> ();
-        t.insert<ixx> ();
-        t.insert<txx> ();
-      }
-
-      // Register rules.
-      //
+      if (first)
       {
-        using namespace bin;
-
-        auto& r (b.rules);
-
-        // We register for configure so that we detect unresolved imports
-        // during configuration rather that later, e.g., during update.
-        //
-        // @@ Should we check if install module was loaded (see bin)?
-        //
-
-        r.insert<obje> (perform_update_id, "cxx.compile", compile::instance);
-        r.insert<obje> (perform_clean_id, "cxx.compile", compile::instance);
-        r.insert<obje> (configure_update_id, "cxx.compile", compile::instance);
+        config_module& cm (*r.modules.lookup<config_module> ("cxx.config"));
 
-        r.insert<exe>  (perform_update_id, "cxx.link", link::instance);
-        r.insert<exe>  (perform_clean_id, "cxx.link", link::instance);
-        r.insert<exe>  (configure_update_id, "cxx.link", link::instance);
+        cc::data d {
+          cm,
 
-        r.insert<exe>  (perform_install_id, "cxx.install", install::instance);
+          "cxx.compile",
+          "cxx.link",
+          "cxx.install",
 
-        // Only register static object/library rules if the bin.ar module is
-        // loaded (by us or by the user).
-        //
-        if (cast_false<bool> (b["bin.ar.loaded"]))
-        {
-          r.insert<obja> (perform_update_id, "cxx.compile", compile::instance);
-          r.insert<obja> (perform_clean_id, "cxx.compile", compile::instance);
-          r.insert<obja> (configure_update_id, "cxx.compile", compile::instance);
+          cast<string> (r[cm.x_id]),
+          cast<string> (r[cm.x_target]),
+          cast<string> (r[cm.x_target_system]),
+          cast<string> (r[cm.x_target_class]),
 
-          r.insert<liba> (perform_update_id, "cxx.link", link::instance);
-          r.insert<liba> (perform_clean_id, "cxx.link", link::instance);
-          r.insert<liba> (configure_update_id, "cxx.link", link::instance);
+          cxx::static_type,
+          hdr,
+          inc
+        };
 
-          r.insert<liba> (perform_install_id, "cxx.install", install::instance);
-        }
-
-        r.insert<objs> (perform_update_id, "cxx.compile", compile::instance);
-        r.insert<objs> (perform_clean_id, "cxx.compile", compile::instance);
-        r.insert<objs> (configure_update_id, "cxx.compile", compile::instance);
-
-        r.insert<libs> (perform_update_id, "cxx.link", link::instance);
-        r.insert<libs> (perform_clean_id, "cxx.link", link::instance);
-        r.insert<libs> (configure_update_id, "cxx.link", link::instance);
-
-        r.insert<libs> (perform_install_id, "cxx.install", install::instance);
+        assert (m == nullptr);
+        m.reset (new module (move (d)));
       }
 
-      // Configure "installability" of our target types.
-      //
-      using namespace install;
-
-      install_path<hxx> (b, dir_path ("include")); // Into install.include.
-      install_path<ixx> (b, dir_path ("include"));
-      install_path<txx> (b, dir_path ("include"));
-      install_path<h>   (b, dir_path ("include"));
-
+      static_cast<module&> (*m).init (r, b, loc, first, hints);
       return true;
     }
   }
diff --git a/build2/cxx/target b/build2/cxx/target
index 154ec24..0239c25 100644
--- a/build2/cxx/target
+++ b/build2/cxx/target
@@ -9,11 +9,15 @@
 #include <build2/utility>
 
 #include <build2/target>
+#include <build2/cc/target>
 
 namespace build2
 {
   namespace cxx
   {
+    using cc::h;
+    using cc::c;
+
     class hxx: public file
     {
     public:
@@ -53,28 +57,6 @@ namespace build2
       static const target_type static_type;
       virtual const target_type& dynamic_type () const {return static_type;}
     };
-
-    //@@ TMP: should be in c-common or some such.
-    //
-    class h: public file
-    {
-    public:
-      using file::file;
-
-    public:
-      static const target_type static_type;
-      virtual const target_type& dynamic_type () const {return static_type;}
-    };
-
-    class c: public file
-    {
-    public:
-      using file::file;
-
-    public:
-      static const target_type static_type;
-      virtual const target_type& dynamic_type () const {return static_type;}
-    };
   }
 }
 
diff --git a/build2/cxx/target.cxx b/build2/cxx/target.cxx
index 22ace50..30afd89 100644
--- a/build2/cxx/target.cxx
+++ b/build2/cxx/target.cxx
@@ -59,29 +59,5 @@ namespace build2
       &search_file,
       false
     };
-
-    extern const char h_ext_def[] = "h";
-    const target_type h::static_type
-    {
-      "h",
-      &file::static_type,
-      &target_factory<h>,
-      &target_extension_var<ext_var, h_ext_def>,
-      nullptr,
-      &search_file,
-      false
-    };
-
-    extern const char c_ext_def[] = "c";
-    const target_type c::static_type
-    {
-      "c",
-      &file::static_type,
-      &target_factory<c>,
-      &target_extension_var<ext_var, c_ext_def>,
-      nullptr,
-      &search_file,
-      false
-    };
   }
 }
diff --git a/build2/cxx/utility b/build2/cxx/utility
deleted file mode 100644
index 7333af6..0000000
--- a/build2/cxx/utility
+++ /dev/null
@@ -1,42 +0,0 @@
-// file      : build2/cxx/utility -*- C++ -*-
-// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#ifndef BUILD2_CXX_UTILITY
-#define BUILD2_CXX_UTILITY
-
-#include <build2/types>
-#include <build2/utility>
-
-#include <build2/target>
-
-#include <build2/cxx/common>
-
-namespace build2
-{
-  namespace cxx
-  {
-    // T is either target or scope.
-    //
-    template <typename T>
-    void
-    append_std (cstrings&, scope& rs, const string& cid, T&, string& storage);
-
-    template <typename T>
-    void
-    hash_std (sha256&, scope& rs, const string& cid, T&);
-
-    // Append or hash library options from one of the cxx.export.* variables
-    // recursively, prerequisite libraries first.
-    //
-    void
-    append_lib_options (cstrings&, target&, const char* variable, lorder);
-
-    void
-    hash_lib_options (sha256&, target&, const char* variable, lorder);
-  }
-}
-
-#include <build2/cxx/utility.ixx>
-
-#endif // BUILD2_CXX_UTILITY
diff --git a/build2/cxx/utility.cxx b/build2/cxx/utility.cxx
deleted file mode 100644
index 7aae6ac..0000000
--- a/build2/cxx/utility.cxx
+++ /dev/null
@@ -1,109 +0,0 @@
-// file      : build2/cxx/utility.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <build2/cxx/utility>
-
-#include <build2/bin/target>
-
-using namespace std;
-
-namespace build2
-{
-  namespace cxx
-  {
-    // Return true if there is an option (stored in s).
-    //
-    bool
-    translate_std (scope& rs, const string& cid, const value& val, string& s)
-    {
-      const string& v (cast<string> (val));
-
-      if (cid == "msvc")
-      {
-        // C++ standard-wise, with VC++ you get what you get. The question is
-        // whether we should verify that the requested standard is provided by
-        // this VC++ version. And if so, from which version should we say VC++
-        // supports 11, 14, and 17? We should probably be as loose as possible
-        // here since the author will always be able to tighten (but not
-        // loosen) this in the buildfile (i.e., detect unsupported versions).
-        //
-        // For now we are not going to bother doing this for C++03.
-        //
-        if (v != "98" && v != "03")
-        {
-          uint64_t cver (cast<uint64_t> (rs["cxx.version.major"]));
-
-          // @@ Is mapping for 14 and 17 correct? Maybe Update 2 for 14?
-          //
-          if ((v == "11" && cver < 16) || // C++11 since VS2010/10.0.
-              (v == "14" && cver < 19) || // C++14 since VS2015/14.0.
-              (v == "17" && cver < 20))   // C++17 since VS20??/15.0.
-          {
-            fail << "C++" << v << " is not supported by "
-                 << cast<string> (rs["cxx.signature"]) <<
-              info << "required by " << rs.out_path ();
-          }
-        }
-
-        return false;
-      }
-      else
-      {
-        // Translate 11 to 0x, 14 to 1y, and 17 to 1z for compatibility with
-        // older versions of the compilers.
-        //
-        s = "-std=";
-
-        if (v == "98")
-          s += "c++98";
-        else if (v == "03")
-          s += "c++03";
-        else if (v == "11")
-          s += "c++0x";
-        else if (v == "14")
-          s += "c++1y";
-        else if (v == "17")
-          s += "c++1z";
-        else
-          s += v; // In case the user specifies something like 'gnu++17'.
-
-        return true;
-      }
-    }
-
-    void
-    append_lib_options (cstrings& args, target& l, const char* var, lorder lo)
-    {
-      using namespace bin;
-
-      for (target* t: l.prerequisite_targets)
-      {
-        if (lib* l = t->is_a<lib> ())
-          t = &link_member (*l, lo); // Pick one of the members.
-
-        if (t->is_a<liba> () || t->is_a<libs> ())
-          append_lib_options (args, *t, var, lo);
-      }
-
-      append_options (args, l, var);
-    }
-
-    void
-    hash_lib_options (sha256& csum, target& l, const char* var, lorder lo)
-    {
-      using namespace bin;
-
-      for (target* t: l.prerequisite_targets)
-      {
-        if (lib* l = t->is_a<lib> ())
-          t = &link_member (*l, lo); // Pick one of the members.
-
-        if (t->is_a<liba> () || t->is_a<libs> ())
-          hash_lib_options (csum, *t, var, lo);
-      }
-
-      hash_options (csum, l, var);
-    }
-  }
-}
diff --git a/build2/cxx/utility.ixx b/build2/cxx/utility.ixx
deleted file mode 100644
index c624e87..0000000
--- a/build2/cxx/utility.ixx
+++ /dev/null
@@ -1,33 +0,0 @@
-// file      : build2/cxx/utility.ixx -*- C++ -*-
-// copyright : Copyright (c) 2014-2016 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-namespace build2
-{
-  namespace cxx
-  {
-    bool
-    translate_std (scope&, const string&, const value&, string&);
-
-    template <typename T>
-    inline void
-    append_std (cstrings& args, scope& rs, const string& cid, T& t, string& s)
-    {
-      if (auto l = t["cxx.std"])
-        if (translate_std (rs, cid, *l, s))
-          args.push_back (s.c_str ());
-    }
-
-    template <typename T>
-    inline void
-    hash_std (sha256& csum, scope& rs, const string& cid, T& t)
-    {
-      if (auto l = t["cxx.std"])
-      {
-        string s;
-        if (translate_std (rs, cid, *l, s))
-          csum.append (s);
-      }
-    }
-  }
-}
diff --git a/build2/diagnostics b/build2/diagnostics
index 8aedf13..5441df1 100644
--- a/build2/diagnostics
+++ b/build2/diagnostics
@@ -259,14 +259,18 @@ namespace build2
   struct simple_prologue_base
   {
     explicit
-    simple_prologue_base (const char* type, const char* name, uint16_t sverb)
-        : type_ (type), name_ (name), sverb_ (sverb) {}
+    simple_prologue_base (const char* type,
+                          const char* mod,
+                          const char* name,
+                          uint16_t sverb)
+        : type_ (type), mod_ (mod), name_ (name), sverb_ (sverb) {}
 
     void
     operator() (const diag_record& r) const;
 
   private:
     const char* type_;
+    const char* mod_;
     const char* name_;
     const uint16_t sverb_;
   };
@@ -290,16 +294,18 @@ namespace build2
   struct location_prologue_base
   {
     location_prologue_base (const char* type,
+                            const char* mod,
                             const char* name,
                             const location& l,
                             uint16_t sverb)
-        : type_ (type), name_ (name), loc_ (l), sverb_ (sverb) {}
+        : type_ (type), mod_ (mod), name_ (name), loc_ (l), sverb_ (sverb) {}
 
     void
     operator() (const diag_record& r) const;
 
   private:
     const char* type_;
+    const char* mod_;
     const char* name_;
     const location loc_;
     const uint16_t sverb_;
@@ -311,23 +317,24 @@ namespace build2
     explicit
     basic_mark_base (uint16_t (*sverb) (),
                      const char* type,
+                     const char* mod = nullptr,
                      const char* name = nullptr,
                      const void* data = nullptr,
                      diag_epilogue epilogue = nullptr)
         : sverb_ (sverb),
-          type_ (type), name_ (name), data_ (data),
+          type_ (type), mod_ (mod), name_ (name), data_ (data),
           epilogue_ (epilogue) {}
 
     simple_prologue
     operator() () const
     {
-      return simple_prologue (epilogue_, type_, name_, sverb_ ());
+      return simple_prologue (epilogue_, type_, mod_, name_, sverb_ ());
     }
 
     location_prologue
     operator() (const location& l) const
     {
-      return location_prologue (epilogue_, type_, name_, l, sverb_ ());
+      return location_prologue (epilogue_, type_, mod_, name_, l, sverb_ ());
     }
 
     template <typename L>
@@ -335,12 +342,13 @@ namespace build2
     operator() (const L& l) const
     {
       return location_prologue (
-        epilogue_, type_, name_, get_location (l, data_), sverb_ ());
+        epilogue_, type_, mod_, name_, get_location (l, data_), sverb_ ());
     }
 
   protected:
     uint16_t (*sverb_) ();
     const char* type_;
+    const char* mod_;
     const char* name_;
     const void* data_;
     const diag_epilogue epilogue_;
@@ -358,8 +366,15 @@ namespace build2
   {
     explicit
     trace_mark_base (const char* name, const void* data = nullptr)
-        : basic_mark_base ([]() {return stream_verb_max;}, "trace", name, data)
-    {}
+        : trace_mark_base (nullptr, name, data) {}
+
+    trace_mark_base (const char* mod,
+                     const char* name,
+                     const void* data = nullptr)
+        : basic_mark_base ([]() {return stream_verb_max;},
+                           "trace",
+                           mod, name,
+                           data) {}
   };
   typedef diag_mark<trace_mark_base> trace_mark;
 
@@ -372,8 +387,11 @@ namespace build2
   {
     explicit
     fail_mark_base (const void* data = nullptr)
-        : basic_mark_base (&stream_verb_map, "error", nullptr, data, &epilogue)
-    {}
+        : basic_mark_base (&stream_verb_map,
+                           "error",
+                           nullptr, nullptr,
+                           data,
+                           &epilogue) {}
 
     static void
     epilogue (const diag_record&) {throw E ();}
diff --git a/build2/diagnostics.cxx b/build2/diagnostics.cxx
index 7b60d05..1265f73 100644
--- a/build2/diagnostics.cxx
+++ b/build2/diagnostics.cxx
@@ -97,6 +97,9 @@ namespace build2
     if (type_ != nullptr)
       r << type_ << ": ";
 
+    if (mod_ != nullptr)
+      r << mod_ << "::";
+
     if (name_ != nullptr)
       r << name_ << ": ";
   }
@@ -119,6 +122,9 @@ namespace build2
     if (type_ != nullptr)
       r << type_ << ": ";
 
+    if (mod_ != nullptr)
+      r << mod_ << "::";
+
     if (name_ != nullptr)
       r << name_ << ": ";
   }
diff --git a/build2/prerequisite b/build2/prerequisite
index 7c913f3..e53bb41 100644
--- a/build2/prerequisite
+++ b/build2/prerequisite
@@ -130,6 +130,9 @@ namespace build2
     template <typename T>
     bool
     is_a () const {return type.is_a<T> ();}
+
+    bool
+    is_a (const target_type_type& tt) const {return type.is_a (tt);}
   };
 
   inline bool
diff --git a/build2/rule b/build2/rule
index 03e4bf2..6d4a580 100644
--- a/build2/rule
+++ b/build2/rule
@@ -13,6 +13,9 @@
 
 namespace build2
 {
+  // @@ This is an ugly mess that is overdue for redesign. Perhaps
+  //    something similar to variable value storage?
+  //
   class match_result
   {
   public:
@@ -56,6 +59,14 @@ namespace build2
     {
       return target != nullptr || prerequisite != nullptr;
     }
+
+    template <typename T>
+    T&
+    as_target () const
+    {
+      return static_cast<T&> (
+        target != nullptr ? *target : *prerequisite->target);
+    }
   };
 
   class rule
diff --git a/build2/target b/build2/target
index 7a50a19..103b719 100644
--- a/build2/target
+++ b/build2/target
@@ -68,6 +68,11 @@ namespace build2
   // this case the returned by the recipe value is still used as the resulting
   // target state so it should match the group's state.
   //
+  // Note that max size for the "small capture optimization" in std::function
+  // ranges (in pointer sizes) from 0 (GCC prior to 5) to 2 (GCC 5) to 6 (VC
+  // 14u2). With the size ranging (in bytes for 64-bit target) from 32 (GCC)
+  // to 64 (VC).
+  //
   using recipe_function = target_state (action, target&);
   using recipe = function<recipe_function>;
 
@@ -471,6 +476,9 @@ namespace build2
     const T*
     is_a () const {return dynamic_cast<const T*> (this);}
 
+    bool
+    is_a (const target_type& tt) const {return type ().is_a (tt);}
+
     // Dynamic derivation to support define.
     //
     const target_type* derived_type = nullptr;
@@ -622,8 +630,9 @@ namespace build2
   //
   struct prerequisite_member
   {
-    typedef build2::target target_type;
-    typedef build2::prerequisite prerequisite_type;
+    using target_type = build2::target;
+    using prerequisite_type = build2::prerequisite;
+    using target_type_type = build2::target_type;
 
     prerequisite_ref& prerequisite;
     target_type* target;
@@ -637,6 +646,14 @@ namespace build2
         : prerequisite.get ().is_a<T> ();
     }
 
+    bool
+    is_a (const target_type_type& tt) const
+    {
+      return target != nullptr
+        ? target->is_a (tt)
+        : prerequisite.get ().is_a (tt);
+    }
+
     prerequisite_key
     key () const
     {
@@ -645,7 +662,7 @@ namespace build2
         : prerequisite.get ().key ();
     }
 
-    const build2::target_type&
+    const target_type_type&
     type () const
     {
       return target != nullptr ? target->type () : prerequisite.get ().type;
diff --git a/build2/target-type b/build2/target-type
index 6006b2c..6140ab1 100644
--- a/build2/target-type
+++ b/build2/target-type
@@ -46,12 +46,18 @@ namespace build2
     target* (*search) (const prerequisite_key&);
     bool see_through; // A group with the default "see through" semantics.
 
-    bool
-    is_a (const target_type&) const; // Defined in target.cxx
-
     template <typename T>
     bool
     is_a () const {return is_a (T::static_type);}
+
+    bool
+    is_a (const target_type& tt) const
+    {
+      return this == &tt || (base != nullptr && is_a_base (tt));
+    }
+
+    bool
+    is_a_base (const target_type&) const; // Defined in target.cxx
   };
 
   inline bool
@@ -97,12 +103,16 @@ namespace build2
   class target_type_map: public target_type_map_base
   {
   public:
-    void
-    insert (const target_type& tt) {emplace (tt.name, target_type_ref (tt));}
+    const target_type&
+    insert (const target_type& tt)
+    {
+      emplace (tt.name, target_type_ref (tt));
+      return tt;
+    }
 
     template <typename T>
-    void
-    insert () {insert (T::static_type);}
+    const target_type&
+    insert () {return insert (T::static_type);}
   };
 }
 
diff --git a/build2/target.cxx b/build2/target.cxx
index a0283b0..7a33dbc 100644
--- a/build2/target.cxx
+++ b/build2/target.cxx
@@ -18,10 +18,10 @@ namespace build2
   // target_type
   //
   bool target_type::
-  is_a (const target_type& tt) const
+  is_a_base (const target_type& tt) const
   {
-    for (const target_type* p (this); p != nullptr; p = p->base)
-      if (*p == tt)
+    for (const target_type* b (base); b != nullptr; b = b->base)
+      if (*b == tt)
         return true;
 
     return false;
diff --git a/build2/utility b/build2/utility
index 4c49be5..3ecceed 100644
--- a/build2/utility
+++ b/build2/utility
@@ -146,13 +146,23 @@ namespace build2
   // Append all the values from a variable to the C-string list. T is either
   // target or scope. The variable is expected to be of type strings.
   //
+  struct variable;
+
+  template <typename T>
+  void
+  append_options (cstrings&, T&, const variable&);
+
+  template <typename T>
+  void
+  append_options (cstrings&, T&, const char*);
+
   template <typename T>
   void
-  append_options (cstrings&, T&, const char* variable);
+  hash_options (sha256&, T&, const variable&);
 
   template <typename T>
   void
-  hash_options (sha256&, T&, const char* variable);
+  hash_options (sha256&, T&, const char*);
 
   // As above but from the strings value directly.
   //
@@ -178,6 +188,13 @@ namespace build2
   bool
   find_option (const char* option,
                T&,
+               const variable&,
+               bool ignore_case = false);
+
+  template <typename T>
+  bool
+  find_option (const char* option,
+               T&,
                const char* variable,
                bool ignore_case = false);
 
@@ -194,6 +211,13 @@ namespace build2
   //
   template <typename T>
   bool
+  find_options (initializer_list<const char*>,
+                T&,
+                const variable&,
+                bool = false);
+
+  template <typename T>
+  bool
   find_options (initializer_list<const char*>, T&, const char*, bool = false);
 
   bool
@@ -209,6 +233,10 @@ namespace build2
   //
   template <typename T>
   bool
+  find_option_prefix (const char* prefix, T&, const variable&, bool = false);
+
+  template <typename T>
+  bool
   find_option_prefix (const char* prefix, T&, const char*, bool = false);
 
   bool
@@ -226,6 +254,13 @@ namespace build2
   bool
   find_option_prefixes (initializer_list<const char*>,
                         T&,
+                        const variable&,
+                        bool = false);
+
+  template <typename T>
+  bool
+  find_option_prefixes (initializer_list<const char*>,
+                        T&,
                         const char*,
                         bool = false);
 
diff --git a/build2/utility.ixx b/build2/utility.ixx
index f957875..956a726 100644
--- a/build2/utility.ixx
+++ b/build2/utility.ixx
@@ -35,6 +35,13 @@ namespace build2
 
   template <typename T>
   inline void
+  append_options (cstrings& args, T& s, const variable& var)
+  {
+    append_options (args, s[var]);
+  }
+
+  template <typename T>
+  inline void
   append_options (cstrings& args, T& s, const char* var)
   {
     append_options (args, s[var]);
@@ -42,14 +49,27 @@ namespace build2
 
   template <typename T>
   inline void
-  hash_options (sha256& csum, T& s, const char* var)
+  hash_options (sha256& csum, T& s, const variable& var)
   {
+    hash_options (csum, s[var]);
+  }
 
+  template <typename T>
+  inline void
+  hash_options (sha256& csum, T& s, const char* var)
+  {
     hash_options (csum, s[var]);
   }
 
   template <typename T>
   inline bool
+  find_option (const char* o, T& s, const variable& var, bool ic)
+  {
+    return find_option (o, s[var], ic);
+  }
+
+  template <typename T>
+  inline bool
   find_option (const char* o, T& s, const char* var, bool ic)
   {
     return find_option (o, s[var], ic);
@@ -59,6 +79,16 @@ namespace build2
   inline bool
   find_options (initializer_list<const char*> os,
                 T& s,
+                const variable& var,
+                bool ic)
+  {
+    return find_options (os, s[var], ic);
+  }
+
+  template <typename T>
+  inline bool
+  find_options (initializer_list<const char*> os,
+                T& s,
                 const char* var,
                 bool ic)
   {
@@ -67,6 +97,13 @@ namespace build2
 
   template <typename T>
   inline bool
+  find_option_prefix (const char* p, T& s, const variable& var, bool ic)
+  {
+    return find_option_prefix (p, s[var], ic);
+  }
+
+  template <typename T>
+  inline bool
   find_option_prefix (const char* p, T& s, const char* var, bool ic)
   {
     return find_option_prefix (p, s[var], ic);
@@ -76,6 +113,16 @@ namespace build2
   inline bool
   find_option_prefixes (initializer_list<const char*> ps,
                         T& s,
+                        const variable& var,
+                        bool ic)
+  {
+    return find_option_prefixes (ps, s[var], ic);
+  }
+
+  template <typename T>
+  inline bool
+  find_option_prefixes (initializer_list<const char*> ps,
+                        T& s,
                         const char* var,
                         bool ic)
   {
diff --git a/build2/variable b/build2/variable
index 9888aa0..d6be976 100644
--- a/build2/variable
+++ b/build2/variable
@@ -691,7 +691,11 @@ namespace build2
     }
 
     const variable&
-    find (const string& name);
+    find (const string& name); //@@ TODO: Move to operator[], remove.
+                               //@@ ranmae var_pool to varpool or vpool?
+
+    const variable&
+    operator[] (const string& name) {return find (name);}
 
     using variable_pool_base::clear;