Do not define GXX_RTTI macro for C.
This is same as GCC behavior (tested with GCC 4.8.2).

Differential Revision: http://reviews.llvm.org/D16365

llvm-svn: 258850
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index a202996..4ad9a33 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1669,7 +1669,7 @@
   Opts.SjLjExceptions = Args.hasArg(OPT_fsjlj_exceptions);
   Opts.TraditionalCPP = Args.hasArg(OPT_traditional_cpp);
 
-  Opts.RTTI = !Args.hasArg(OPT_fno_rtti);
+  Opts.RTTI = Opts.CPlusPlus && !Args.hasArg(OPT_fno_rtti);
   Opts.RTTIData = Opts.RTTI && !Args.hasArg(OPT_fno_rtti_data);
   Opts.Blocks = Args.hasArg(OPT_fblocks);
   Opts.BlocksRuntimeOptional = Args.hasArg(OPT_fblocks_runtime_optional);