diff --git a/clang/lib/Parse/ParseDeclCXX.cpp b/clang/lib/Parse/ParseDeclCXX.cpp
--- a/clang/lib/Parse/ParseDeclCXX.cpp
+++ b/clang/lib/Parse/ParseDeclCXX.cpp
@@ -2982,9 +2982,11 @@
       ExprResult Init = ParseCXXMemberInitializer(
           ThisDecl, DeclaratorInfo.isDeclarationOfFunction(), EqualLoc);
 
-      if (Init.isInvalid())
+      if (Init.isInvalid()) {
+        if (ThisDecl)
+          ThisDecl->setInvalidDecl();
         SkipUntil(tok::comma, StopAtSemi | StopBeforeMatch);
-      else if (ThisDecl)
+      } else if (ThisDecl)
         Actions.AddInitializerToDecl(ThisDecl, Init.get(), EqualLoc.isInvalid());
     } else if (ThisDecl && DS.getStorageClassSpec() == DeclSpec::SCS_static)
       // No initializer.
diff --git a/clang/test/AST/ast-dump-undeduced-expr.cpp b/clang/test/AST/ast-dump-undeduced-expr.cpp
new file mode 100644
--- /dev/null
+++ b/clang/test/AST/ast-dump-undeduced-expr.cpp
@@ -0,0 +1,7 @@
+// RUN: not %clang_cc1 -triple x86_64-unknown-unknown -ast-dump %s | FileCheck %s
+
+struct Foo {
+  static constexpr auto Bar = ;
+};
+
+// CHECK: -VarDecl {{.*}} invalid Bar 'const auto' static constexpr
diff --git a/clang/test/SemaCXX/cxx11-crashes.cpp b/clang/test/SemaCXX/cxx11-crashes.cpp
--- a/clang/test/SemaCXX/cxx11-crashes.cpp
+++ b/clang/test/SemaCXX/cxx11-crashes.cpp
@@ -104,3 +104,20 @@
   bool baz() { return __has_nothrow_constructor(B); }
   bool qux() { return __has_nothrow_copy(B); }
 }
+
+namespace undeduced_field {
+template<class T>
+struct Foo {
+  typedef T type;
+};
+
+struct Bar {
+  Bar();
+  // The missing expression makes A undeduced.
+  static constexpr auto A = ;  // expected-error {{expected expression}}
+  Foo<decltype(A)>::type B;  // The type of B is also undeduced (wrapped in Elaborated).
+};
+
+// This used to crash when trying to get the layout of B.
+Bar x;
+}