Don't crash when mangling types defined in ObjC class extensions.

The original test case here was mangling a type name for TBAA,
but we can provoke this in C++11 easily enough.

rdar://13434937

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179153 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 9 insertions, 0 deletions

diff --git a/lib/AST/ItaniumMangle.cpp b/lib/AST/ItaniumMangle.cpp
index 21c499317f..0f4881e24e 100644
--- a/lib/AST/ItaniumMangle.cpp
+++ b/lib/AST/ItaniumMangle.cpp
@@ -1095,6 +1095,15 @@ void CXXNameMangler::mangleUnqualifiedName(const NamedDecl *ND,
       mangleSourceName(FD->getIdentifier());
       break;
     }
+
+    // Class extensions have no name as a category, and it's possible
+    // for them to be the semantic parent of certain declarations
+    // (primarily, tag decls defined within declarations).  Such
+    // declarations will always have internal linkage, so the name
+    // doesn't really matter, but we shouldn't crash on them.  For
+    // safety, just handle all ObjC containers here.
+    if (isa<ObjCContainerDecl>(ND))
+      break;
     
     // We must have an anonymous struct.
     const TagDecl *TD = cast<TagDecl>(ND);