Ensure we diagnose long long literals in C90 mode.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@41581 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Sema/SemaExpr.cpp b/Sema/SemaExpr.cpp
index b613cd9..272fc6f 100644
--- a/Sema/SemaExpr.cpp
+++ b/Sema/SemaExpr.cpp
@@ -156,6 +156,11 @@
   } else {
     QualType t;
 
+    // long long is a C99 feature.
+    if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x &&
+	Literal.isLongLong)
+      Diag(Tok.getLocation(), diag::ext_longlong);
+
     // Get the value in the widest-possible width.
     llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(Tok.getLocation()), 0);