Support for C1x _Atomic specifier (see testcase).  This is primarily being committed at the moment to help support C++0x <atomic>, but it should be a solid base for implementing the full specification of C1x _Atomic.

Thanks to Jeffrey Yasskin for the thorough review!

llvm-svn: 141330
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 718a19b..534cd48 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -3011,7 +3011,8 @@
   case DeclSpec::TST_typename:
   case DeclSpec::TST_typeofType:
   case DeclSpec::TST_decltype:
-  case DeclSpec::TST_underlyingType: {
+  case DeclSpec::TST_underlyingType:
+  case DeclSpec::TST_atomic: {
     // Grab the type from the parser.
     TypeSourceInfo *TSI = 0;
     QualType T = S.GetTypeFromParser(DS.getRepAsType(), &TSI);