Don't error on C++ linkage; if we don't support that, there are 
serious issues :)

llvm-svn: 77800
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index a5b0dac..ec9a97a 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1493,7 +1493,8 @@
 
 // EmitLinkageSpec - Emit all declarations in a linkage spec.
 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) {
-  if (LSD->getLanguage() != LinkageSpecDecl::lang_c) {
+  if (LSD->getLanguage() != LinkageSpecDecl::lang_c &&
+      LSD->getLanguage() != LinkageSpecDecl::lang_cxx) {
     ErrorUnsupported(LSD, "linkage spec");
     return;
   }