Don't create targets for non-existent source files

3 files changed, 28 insertions, 18 deletions

diff --git a/libbuild2/algorithm.cxx b/libbuild2/algorithm.cxx
index cb63e87..8f399dd 100644
--- a/libbuild2/algorithm.cxx
+++ b/libbuild2/algorithm.cxx
@@ -65,7 +65,13 @@ namespace build2
     if (const target* pt = pk.tk.type->search (t, pk))
       return *pt;
 
-    return create_new_target (t.ctx, pk);
+    if (pk.tk.out->empty ())
+      return create_new_target (t.ctx, pk);
+
+    // If this is triggered, then you are probably not passing scope to
+    // search() (which leads to search_existing_file() being skipped).
+    //
+    fail << "no existing source file for prerequisite " << pk << endf;
   }
 
   pair<target&, ulock>
@@ -76,7 +82,13 @@ namespace build2
     if (const target* pt = pk.tk.type->search (t, pk))
       return {const_cast<target&> (*pt), ulock ()};
 
-    return create_new_target_locked (t.ctx, pk);
+    if (pk.tk.out->empty ())
+      return create_new_target_locked (t.ctx, pk);
+
+    // If this is triggered, then you are probably not passing scope to
+    // search() (which leads to search_existing_file() being skipped).
+    //
+    fail << "no existing source file for prerequisite " << pk << endf;
   }
 
   const target*
diff --git a/libbuild2/dyndep.cxx b/libbuild2/dyndep.cxx
index 94d2028..9816ad6 100644
--- a/libbuild2/dyndep.cxx
+++ b/libbuild2/dyndep.cxx
@@ -445,7 +445,7 @@ namespace build2
     // The directory is only moved from if insert is true. Note that it must
     // be normalized.
     //
-    auto find = [&trace, what, &t,
+    auto find = [&trace, what, &bs, &t,
                  &map_extension,
                  &fallback] (dir_path&& d,
                              path&& f,
@@ -603,7 +603,7 @@ namespace build2
       // @@ OPT: move d, out, n
       //
       if (r == nullptr && insert)
-        r = &search (t, *tts[0], d, out, n, &e);
+        r = &search (t, *tts[0], d, out, n, &e, &bs);
 
       return static_cast<const file*> (r);
     };
diff --git a/libbuild2/search.cxx b/libbuild2/search.cxx
index c2f7de4..3bdb503 100644
--- a/libbuild2/search.cxx
+++ b/libbuild2/search.cxx
@@ -231,6 +231,12 @@ namespace build2
 
     const target_key& tk (pk.tk);
 
+    // If out is present, then it means the target is in src and we shouldn't
+    // be creating new targets in src, should we? Feels like this should not
+    // even be called if out is not empty.
+    //
+    assert (tk.out->empty ());
+
     // We default to the target in this directory scope.
     //
     dir_path d;
@@ -251,13 +257,6 @@ namespace build2
     //
     // More often insert than find, so skip find in insert().
     //
-    // @@ OUT: same story as in search_existing_target() re out. Maybe not:
-    //         if out is present, then it means the target is in src and we
-    //         shouldn't be creating new targets in src, should we? Feels
-    //         like this should not even be called in out is not empty.
-    //
-    //assert (tk.out->empty ()); @@ TMP
-
     auto r (ctx.targets.insert (*tk.type,
                                 move (d),
                                 *tk.out,
@@ -280,6 +279,12 @@ namespace build2
 
     const target_key& tk (pk.tk);
 
+    // If out is present, then it means the target is in src and we shouldn't
+    // be creating new targets in src, should we? Feels like this should not
+    // even be called if out is not empty.
+    //
+    assert (tk.out->empty ());
+
     // We default to the target in this directory scope.
     //
     dir_path d;
@@ -300,13 +305,6 @@ namespace build2
     //
     // More often insert than find, so skip find in insert_locked().
     //
-    // @@ OUT: same story as in search_existing_target() re out. Maybe not:
-    //         if out is present, then it means the target is in src and we
-    //         shouldn't be creating new targets in src, should we? Feels
-    //         like this should not even be called in out is not empty.
-    //
-    //assert (tk.out->empty ()); @@ TMP
-
     auto r (ctx.targets.insert_locked (*tk.type,
                                        move (d),
                                        *tk.out,