Provide a common set of routines in Version.h that return Subversion

branch/revision information. Use that information in the driver,
rather than one-off branch/revision computation. 

llvm-svn: 83321

1 files changed, 2 insertions, 16 deletions

diff --git a/clang/lib/Basic/Version.cpp b/clang/lib/Basic/Version.cpp
index 3a51ccb5..9699ee4 100644
--- a/clang/lib/Basic/Version.cpp
+++ b/clang/lib/Basic/Version.cpp
@@ -39,24 +39,10 @@ const char *getClangSubversionPath() {
 
 unsigned getClangSubversionRevision() {
 #ifndef SVN_REVISION
+  // Subversion was not available at build time?
   return 0;
 #else
-  // What follows is an evil trick. We can end up getting three different
-  // kinds of results when asking for the Subversion information:
-  //   - if SVN_REVISION is a number, we return that number (adding 0 to it is
-  //     harmless).
-  //   - if SVN_REVISION is "exported" (for an tree without any Subversion 
-  //     info), we end up referencing the local variable "exported" and adding
-  //     zero to it, and we return 0.
-  //   - if SVN_REVISION is empty (because "svn info" returned no results),
-  //     the "+" turns into a unary "+" operator and we return 0.
-  //
-  // Making this less ugly requires doing more computation in the CMake- and
-  // Makefile-based build systems, with all sorts of checking to make sure we
-  // don't end up breaking this build. It's better this way. Really.
-  const unsigned exported = 0;
-  (void)exported;
-  return SVN_REVISION + 0;
+  return strtol(SVN_REVISION, 0, 10);
 #endif
 }