Make sure that forward declarations are marked as such in the debug info
for the structure type.

rdar://10499337

llvm-svn: 145461
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index efffd2c..922b725 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -1214,7 +1214,8 @@
   if (ID->isForwardDecl()) {
     llvm::DIType FwdDecl =
       DBuilder.createStructType(Unit, ID->getName(),
-                                DefUnit, Line, 0, 0, 0,
+                                DefUnit, Line, 0, 0,
+                                llvm::DIDescriptor::FlagFwdDecl,
                                 llvm::DIArray(), RuntimeLang);
     return FwdDecl;
   }