Don't attempt to poke into an invalid field's class type

to mark its destructors as referenced which may cause 
a crash. Fixes radar 7896920

llvm-svn: 103953

clang/lib/Sema/SemaDeclCXX.cpp

@@ -2139,7 +2139,8 @@ Sema::MarkBaseAndMemberDestructorsReferenced(SourceLocation Location,
   for (CXXRecordDecl::field_iterator I = ClassDecl->field_begin(),
        E = ClassDecl->field_end(); I != E; ++I) {
     FieldDecl *Field = *I;
-    
+    if (Field->isInvalidDecl())
+      continue;
     QualType FieldType = Context.getBaseElementType(Field->getType());
     
     const RecordType* RT = FieldType->getAs<RecordType>();

clang/test/SemaCXX/invalid-instantiated-field-decl.cpp

@@ -0,0 +1,35 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+template <typename T>
+class SmallVectorImpl  {
+public:
+  explicit SmallVectorImpl(unsigned N) {
+  }
+
+  ~SmallVectorImpl() { }
+
+};
+
+template <typename T, unsigned N>
+class SmallVector : public SmallVectorImpl<T> {
+  typedef typename SmallVectorImpl<T>::U U; // expected-error {{no type named 'U' in 'SmallVectorImpl<CallSite>'}}
+  enum {
+
+    MinUs = (static_cast<unsigned int>(sizeof(T))*N +	// expected-error {{invalid application of 'sizeof' to an incomplete type 'CallSite'}}
+             static_cast<unsigned int>(sizeof(U)) - 1) /
+            static_cast<unsigned int>(sizeof(U)),
+    NumInlineEltsElts = MinUs 
+  };
+  U InlineElts[NumInlineEltsElts];
+public:
+  SmallVector() : SmallVectorImpl<T>(NumInlineEltsElts) {
+  }
+
+};
+
+class CallSite;	// expected-note {{forward declaration of 'CallSite'}}
+class InlineFunctionInfo {
+public:
+  explicit InlineFunctionInfo() {}
+  SmallVector<CallSite, 2> DevirtualizedCalls;	// expected-note {{in instantiation of template class 'SmallVector<CallSite, 2>' requested}}
+};