Add bootstrap script, INSTALL file

4 files changed, 65 insertions, 5 deletions

diff --git a/INSTALL b/INSTALL
new file mode 100644
index 0000000..9669735
--- /dev/null
+++ b/INSTALL
@@ -0,0 +1,32 @@
+Currently, to use build2 you will need a C++ compiler with C++14 support.
+This may be relaxed later to only require C++11. For now, gcc 4.9.0 or
+later and clang 3.5.0 or later are known to work.
+
+build2 is self-hosted, which means that unless you have obtained a pre-
+built binary of build2 from somewhere else, you will need to bootstrap
+it. To accomplish this, use the 'bootstrap' shell script found in the
+root directory of the build2 project. The following is a recommended
+sequence of steps:
+
+1. Execute 'bootstrap' specifying the C++ compiler to be used if necessary
+   (default is 'g++'). For example:
+
+   $ ./bootstrap --cxx clang++-3.5
+
+   Once the script completes successfully, the build2 binary is saved
+   as 'build/b-boot'.
+
+2. Next, build the build2 binary using the bootstrapped binary from step
+   1 above, again specifying the C++ compiler if necessary, for example:
+
+   $ build/b-boot config.cxx=clang++-3.5
+
+   The result of this command is saved as 'build/b'.
+
+3. Finally, rebuild the build2 binary using the binary built at step 2
+   above, and verify that they are identical. For example:
+
+   $ mv build/b build/b-prev
+   $ build/b-prev config.cxx=clang++-3.5 clean
+   $ build/b-prev config.cxx=clang++-3.5 configure update
+   $ diff -b build/b build/b-prev
diff --git a/bootstrap b/bootstrap
new file mode 100755
index 0000000..86dcc78
--- /dev/null
+++ b/bootstrap
@@ -0,0 +1,31 @@
+#!/bin/sh
+
+src="build/*.cxx build/config/*.cxx build/bin/*.cxx build/cxx/*.cxx"
+
+cxx=g++
+
+while test $# -ne 0; do
+  case $1 in
+    --help)
+      echo "Usage: $0 [--help] [--cxx <c++-compiler>]" 1>&2
+      echo "See the INSTALL file for details." 1>&2
+      exit 0
+      ;;
+    --cxx)
+      shift
+      if test $# -eq 0; then
+	echo "error: c++ compiler executable expected after --cxx" 1>&2
+	exit 1
+      fi
+      cxx=$1
+      shift
+      ;;
+    *)
+      echo "error: unknown option $1" 1>&2
+      exit 1
+      ;;
+  esac
+done
+
+echo $cxx -std=c++14 -I. -o build/b-boot $src 1>&2
+exec $cxx -std=c++14 -I. -o build/b-boot $src
diff --git a/build/.gitignore b/build/.gitignore
index 6626bcb..62f3460 100644
--- a/build/.gitignore
+++ b/build/.gitignore
@@ -1,4 +1,3 @@
 b
-b-prev
-b-save*
+b-*
 config.build
diff --git a/build/buildfile b/build/buildfile
index 1224548..9ea95d5 100644
--- a/build/buildfile
+++ b/build/buildfile
@@ -2,13 +2,11 @@ config = config/{operation module utility}
 bin = bin/{target rule module}
 cxx = cxx/{target rule module}
 
-exe{b b-prev}: cxx{b algorithm name operation spec scope variable target \
+exe{b}: cxx{b algorithm name operation spec scope variable target \
   prerequisite rule file module context search diagnostics token lexer \
   parser process timestamp path path-io utility filesystem dump options \
   $config $bin $cxx}
 
-.: exe{b b-prev}
-
 #@@ TODO
 #
 # cli --include-with-brackets --include-prefix build --guard-prefix BUILD --hxx-suffix "" options.cli