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

clang/include/clang/Basic/Version.h

@@ -58,6 +58,11 @@ namespace clang {
   ///   which includes the clang version number, the repository version, 
   ///   and the vendor tag.
   std::string getClangFullVersion();
+
+  /// \brief Retrieves a string representing the complete clang version suitable
+  ///   for use in the CPP __VERSION__ macro, which includes the clang version
+  ///   number, the repository version, and the vendor tag.
+  std::string getClangFullCPPVersion();
 }
 
 #endif // LLVM_CLANG_BASIC_VERSION_H

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

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.
 

clang/test/Preprocessor/init.c

@@ -982,7 +982,7 @@
 // SPARC:#define __SIZE_WIDTH__ 32
 // SPARC:#define __UINTMAX_TYPE__ long long unsigned int
 // SPARC:#define __USER_LABEL_PREFIX__ _
-// SPARC:#define __VERSION__ "4.2.1 Compatible Clang Compiler"
+// SPARC:#define __VERSION__ "4.2.1 Compatible
 // SPARC:#define __WCHAR_MAX__ 2147483647
 // SPARC:#define __WCHAR_TYPE__ int
 // SPARC:#define __WCHAR_WIDTH__ 32