5 files changed, 35 insertions, 7 deletions
diff --git a/clang/include/clang/AST/DeclCXX.h b/clang/include/clang/AST/DeclCXX.h
index 56bbbb16910..72fad7c28e4 100644
--- a/clang/include/clang/AST/DeclCXX.h
+++ b/clang/include/clang/AST/DeclCXX.h
@@ -462,6 +462,9 @@ class CXXRecordDecl : public RecordDecl {
     /// \brief Whether this class describes a C++ lambda.
     bool IsLambda : 1;
 
+    /// \brief Whether we are currently parsing base specifiers.
+    bool IsParsingBaseSpecifiers : 1;
+
     /// \brief The number of base class specifiers in Bases.
     unsigned NumBases;
 
@@ -685,6 +688,12 @@ public:
     return data().Polymorphic || data().NumVBases != 0;
   }
 
+  void setIsParsingBaseSpecifiers() { data().IsParsingBaseSpecifiers = true; }
+
+  bool isParsingBaseSpecifiers() const {
+    return data().IsParsingBaseSpecifiers;
+  }
+
   /// \brief Sets the base classes of this struct or class.
   void setBases(CXXBaseSpecifier const * const *Bases, unsigned NumBases);
 
diff --git a/clang/lib/AST/DeclCXX.cpp b/clang/lib/AST/DeclCXX.cpp
index 0ac8b73e306..43d0fca9f92 100644
--- a/clang/lib/AST/DeclCXX.cpp
+++ b/clang/lib/AST/DeclCXX.cpp
@@ -70,7 +70,8 @@ CXXRecordDecl::DefinitionData::DefinitionData(CXXRecordDecl *D)
     ImplicitCopyAssignmentHasConstParam(true),
     HasDeclaredCopyConstructorWithConstParam(false),
     HasDeclaredCopyAssignmentWithConstParam(false),
-    IsLambda(false), NumBases(0), NumVBases(0), Bases(), VBases(),
+    IsLambda(false), IsParsingBaseSpecifiers(false), NumBases(0), NumVBases(0),
+    Bases(), VBases(),
     Definition(D), FirstFriend() {
 }
 
@@ -334,8 +335,10 @@ CXXRecordDecl::setBases(CXXBaseSpecifier const * const *Bases,
     addedClassSubobject(BaseClassDecl);
   }
   
-  if (VBases.empty())
+  if (VBases.empty()) {
+    data().IsParsingBaseSpecifiers = false;
     return;
+  }
 
   // Create base specifier for any direct or indirect virtual bases.
   data().VBases = new (C) CXXBaseSpecifier[VBases.size()];
@@ -346,6 +349,8 @@ CXXRecordDecl::setBases(CXXBaseSpecifier const * const *Bases,
       addedClassSubobject(Type->getAsCXXRecordDecl());
     data().getVBases()[I] = *VBases[I];
   }
+
+  data().IsParsingBaseSpecifiers = false;
 }
 
 void CXXRecordDecl::addedClassSubobject(CXXRecordDecl *Subobj) {
diff --git a/clang/lib/AST/MicrosoftCXXABI.cpp b/clang/lib/AST/MicrosoftCXXABI.cpp
index 359e8648278..6870315b216 100644
--- a/clang/lib/AST/MicrosoftCXXABI.cpp
+++ b/clang/lib/AST/MicrosoftCXXABI.cpp
@@ -93,7 +93,7 @@ static bool usesMultipleInheritanceModel(const CXXRecordDecl *RD) {
 }
 
 MSInheritanceAttr::Spelling CXXRecordDecl::calculateInheritanceModel() const {
-  if (!hasDefinition())
+  if (!hasDefinition() || isParsingBaseSpecifiers())
     return MSInheritanceAttr::Keyword_unspecified_inheritance;
   if (getNumVBases() > 0)
     return MSInheritanceAttr::Keyword_virtual_inheritance;
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 57e6550cec5..ed7908dfc92 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -1431,6 +1431,9 @@ Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
   if (!Class)
     return true;
 
+  // We haven't yet attached the base specifiers.
+  Class->setIsParsingBaseSpecifiers();
+
   // We do not support any C++11 attributes on base-specifiers yet.
   // Diagnose any attributes we see.
   if (!Attributes.empty()) {
diff --git a/clang/test/CodeGenCXX/microsoft-abi-member-pointers.cpp b/clang/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
index 48bc2c721f0..18e8c827eeb 100644
--- a/clang/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
+++ b/clang/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
@@ -1,7 +1,7 @@
-// RUN: %clang_cc1 -fno-rtti -emit-llvm %s -o - -triple=i386-pc-win32 -fms-extensions | FileCheck %s
-// RUN: %clang_cc1 -fno-rtti -emit-llvm %s -o - -triple=x86_64-pc-win32 -fms-extensions | FileCheck %s -check-prefix=X64
-// RUN: %clang_cc1 -fno-rtti -emit-llvm %s -o - -triple=i386-pc-win32 -DINCOMPLETE_VIRTUAL -fms-extensions -verify
-// RUN: %clang_cc1 -fno-rtti -emit-llvm %s -o - -triple=i386-pc-win32 -DINCOMPLETE_VIRTUAL -DMEMFUN -fms-extensions -verify
+// RUN: %clang_cc1 -std=c++11 -fno-rtti -emit-llvm %s -o - -triple=i386-pc-win32 -fms-extensions | FileCheck %s
+// RUN: %clang_cc1 -std=c++11 -fno-rtti -emit-llvm %s -o - -triple=x86_64-pc-win32 -fms-extensions | FileCheck %s -check-prefix=X64
+// RUN: %clang_cc1 -std=c++11 -fno-rtti -emit-llvm %s -o - -triple=i386-pc-win32 -DINCOMPLETE_VIRTUAL -fms-extensions -verify
+// RUN: %clang_cc1 -std=c++11 -fno-rtti -emit-llvm %s -o - -triple=i386-pc-win32 -DINCOMPLETE_VIRTUAL -DMEMFUN -fms-extensions -verify
 // FIXME: Test x86_64 member pointers when codegen no longer asserts on records
 // with virtual bases.
 
@@ -630,6 +630,17 @@ void test() { void (B::*a)() = &B::f; }
 // CHECK: store i8* bitcast (void (%"struct.pr20007_kw::A"*)* @"\01?f@A@pr20007_kw@@QAEXXZ" to i8*)
 }
 
+namespace pr19987 {
+template <typename T>
+struct S {
+  int T::*x;
+};
+
+struct U : S<U> {};
+
+static_assert(sizeof(S<U>::x) == 12, "");
+}
+
 #else
 struct __virtual_inheritance A;
 #ifdef MEMFUN