diff --git a/lib/AST/ItaniumMangle.cpp b/lib/AST/ItaniumMangle.cpp
index 2f9123c..db0df36 100644
--- a/lib/AST/ItaniumMangle.cpp
+++ b/lib/AST/ItaniumMangle.cpp
@@ -405,12 +405,14 @@
   CXXNameMangler(CXXNameMangler &Outer, raw_ostream &Out_)
       : Context(Outer.Context), Out(Out_), NullOut(false),
         Structor(Outer.Structor), StructorType(Outer.StructorType),
-        SeqID(Outer.SeqID), AbiTagsRoot(AbiTags) {}
+        SeqID(Outer.SeqID), FunctionTypeDepth(Outer.FunctionTypeDepth),
+        AbiTagsRoot(AbiTags), Substitutions(Outer.Substitutions) {}
 
   CXXNameMangler(CXXNameMangler &Outer, llvm::raw_null_ostream &Out_)
       : Context(Outer.Context), Out(Out_), NullOut(true),
         Structor(Outer.Structor), StructorType(Outer.StructorType),
-        SeqID(Outer.SeqID), AbiTagsRoot(AbiTags) {}
+        SeqID(Outer.SeqID), FunctionTypeDepth(Outer.FunctionTypeDepth),
+        AbiTagsRoot(AbiTags), Substitutions(Outer.Substitutions) {}
 
 #if MANGLE_CHECKER
   ~CXXNameMangler() {
@@ -458,6 +460,8 @@
   void addSubstitution(QualType T);
   void addSubstitution(TemplateName Template);
   void addSubstitution(uintptr_t Ptr);
+  // Destructive copy substitutions from other mangler.
+  void extendSubstitutions(CXXNameMangler* Other);
 
   void mangleUnresolvedPrefix(NestedNameSpecifier *qualifier,
                               bool recursive = false);
@@ -685,6 +689,10 @@
   // Output name with implicit tags and function encoding from temporary buffer.
   mangleNameWithAbiTags(FD, &AdditionalAbiTags);
   Out << FunctionEncodingStream.str().substr(EncodingPositionStart);
+
+  // Function encoding could create new substitutions so we have to add
+  // temp mangled substitutions to main mangler.
+  extendSubstitutions(&FunctionEncodingMangler);
 }
 
 void CXXNameMangler::mangleFunctionEncodingBareType(const FunctionDecl *FD) {
@@ -4426,6 +4434,14 @@
   Substitutions[Ptr] = SeqID++;
 }
 
+void CXXNameMangler::extendSubstitutions(CXXNameMangler* Other) {
+  assert(Other->SeqID >= SeqID && "Must be superset of substitutions!");
+  if (Other->SeqID > SeqID) {
+    Substitutions.swap(Other->Substitutions);
+    SeqID = Other->SeqID;
+  }
+}
+
 CXXNameMangler::AbiTagList
 CXXNameMangler::makeFunctionReturnTypeTags(const FunctionDecl *FD) {
   // When derived abi tags are disabled there is no need to make any list.
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index fe85a89..3a9eb3e 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -3074,10 +3074,14 @@
     return;
   }
 
+  if (FirstType->isIncompleteType())
+    return;
   uint64_t FirstSize = S.Context.getTypeSize(FirstType);
   uint64_t FirstAlign = S.Context.getTypeAlign(FirstType);
   for (; Field != FieldEnd; ++Field) {
     QualType FieldType = Field->getType();
+    if (FieldType->isIncompleteType())
+      return;
     // FIXME: this isn't fully correct; we also need to test whether the
     // members of the union would all have the same calling convention as the
     // first member of the union. Checking just the size and alignment isn't
diff --git a/test/CodeGenCXX/mangle-abi-tag.cpp b/test/CodeGenCXX/mangle-abi-tag.cpp
index 385a16f..a653ff4 100644
--- a/test/CodeGenCXX/mangle-abi-tag.cpp
+++ b/test/CodeGenCXX/mangle-abi-tag.cpp
@@ -203,3 +203,32 @@
 }
 // A18::operator A[abi:A][abi:B]() but GCC adds the same tags twice!
 // CHECK-DAG: define linkonce_odr {{.+}} @_ZN3A18cv1AB1AB1BEv(
+
+namespace N19 {
+  class A {};
+  class __attribute__((abi_tag("B"))) B {};
+  class D {};
+  class F {};
+
+  template<typename T, B F(T, D)>
+  class C {};
+
+  B foo(A, D);
+}
+void f19_test(N19::C<N19::A,  &N19::foo>, N19::F, N19::D) {
+}
+// f19_test(N19::C<N19::A, &N19::foo[abi:B]>, N19::F, N19::D)
+// CHECK-DAG: define void @_Z8f19_testN3N191CINS_1AEXadL_ZNS_3fooB1BES1_NS_1DEEEEENS_1FES2_(
+
+namespace pr30440 {
+
+template<class F> void g(F);
+template<class ...A> auto h(A ...a)->decltype (g (0, g < a > (a) ...)) {
+}
+// CHECK-DAG: define {{.*}} @_ZN7pr304401hIJEEEDTcl1gLi0Espcl1gIL_ZZNS_1hEDpT_E1aEEfp_EEES2_(
+
+void pr30440_test () {
+  h();
+}
+
+}
diff --git a/test/Sema/transparent-union.c b/test/Sema/transparent-union.c
index 8ef70bb..a1a67df 100644
--- a/test/Sema/transparent-union.c
+++ b/test/Sema/transparent-union.c
@@ -89,3 +89,12 @@
     unsigned int u3;
   } __attribute__((aligned(8)));
 } __attribute__((transparent_union));
+
+union pr30520v { void b; } __attribute__((transparent_union)); // expected-error {{field has incomplete type 'void'}}
+
+union pr30520a { int b[]; } __attribute__((transparent_union)); // expected-error {{field has incomplete type 'int []'}}
+
+// expected-note@+1 2 {{forward declaration of 'struct stb'}}
+union pr30520s { struct stb b; } __attribute__((transparent_union)); // expected-error {{field has incomplete type 'struct stb'}}
+
+union pr30520s2 { int *v; struct stb b; } __attribute__((transparent_union)); // expected-error {{field has incomplete type 'struct stb'}}