Change Clang's __VERSION__ to include the same basic info as in clang -v.

 - Please never ever ever ever write a tool that sniffs this.

llvm-svn: 128599

2 files changed, 19 insertions, 1 deletions

diff --git a/clang/lib/Basic/Version.cpp b/clang/lib/Basic/Version.cpp
index af2f848071b..65cc2581dab 100644
--- a/clang/lib/Basic/Version.cpp
+++ b/clang/lib/Basic/Version.cpp
@@ -91,4 +91,17 @@ std::string getClangFullVersion() {
   return OS.str();
 }
 
+std::string getClangFullCPPVersion() {
+  // The version string we report in __VERSION__ is just a compacted version of
+  // the one we report on the command line.
+  std::string buf;
+  llvm::raw_string_ostream OS(buf);
+#ifdef CLANG_VENDOR
+  OS << CLANG_VENDOR;
+#endif
+  OS << "Clang " CLANG_VERSION_STRING " ("
+     << getClangFullRepositoryVersion() << ')';
+  return OS.str();
+}
+
 } // end namespace clang
diff --git a/clang/lib/Frontend/InitPreprocessor.cpp b/clang/lib/Frontend/InitPreprocessor.cpp
index 3c5be253c7f..928e84b1856 100644
--- a/clang/lib/Frontend/InitPreprocessor.cpp
+++ b/clang/lib/Frontend/InitPreprocessor.cpp
@@ -247,7 +247,12 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
   Builder.defineMacro("__GNUC_PATCHLEVEL__", "1");
   Builder.defineMacro("__GNUC__", "4");
   Builder.defineMacro("__GXX_ABI_VERSION", "1002");
-  Builder.defineMacro("__VERSION__", "\"4.2.1 Compatible Clang Compiler\"");
+
+  // As sad as it is, enough software depends on the __VERSION__ for version
+  // checks that it is necessary to report 4.2.1 (the base GCC version we claim
+  // compatibility with) first.
+  Builder.defineMacro("__VERSION__", "\"4.2.1 Compatible " + 
+                      llvm::Twine(getClangFullCPPVersion()) + "\"");
 
   // Initialize language-specific preprocessor defines.