Index: clang/lib/AST/ItaniumMangle.cpp
===================================================================
--- clang/lib/AST/ItaniumMangle.cpp
+++ clang/lib/AST/ItaniumMangle.cpp
@@ -1317,9 +1317,13 @@
     }
 
     if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) {
+      const RecordType* RT = VD->getType()->getAs<RecordType>();
+      // FIXME:(jbcoe) find out why this check is needed. 
+      if (!RT)
+        break;
+
       // We must have an anonymous union or struct declaration.
-      const RecordDecl *RD =
-        cast<RecordDecl>(VD->getType()->getAs<RecordType>()->getDecl());
+      const RecordDecl *RD = cast<RecordDecl>(RT->getDecl());
 
       // Itanium C++ ABI 5.1.2:
       //
Index: mangled-names-crash.py
===================================================================
--- /dev/null
+++ mangled-names-crash.py
@@ -0,0 +1,20 @@
+from __future__ import print_function
+
+import clang.cindex
+
+
+def traverse(node):
+    print('L:', node.location.line, node.spelling, node.type.spelling, node.mangled_name)
+    for child in node.get_children():
+        traverse(child)
+
+with open('test.cpp', 'w') as o:
+    o.write('''struct S { 
+  void(*g)(void); 
+  void(*f)(void*); 
+};
+''')
+
+index = clang.cindex.Index.create()
+tu = index.parse('test.cpp', args=['-Werror'])
+traverse(tu.cursor)