4 files changed, 81 insertions, 17 deletions
diff --git a/clang/test/CodeGenCXX/dllexport.cpp b/clang/test/CodeGenCXX/dllexport.cpp
index 6232f2c747e..7cef7c2d127 100644
--- a/clang/test/CodeGenCXX/dllexport.cpp
+++ b/clang/test/CodeGenCXX/dllexport.cpp
@@ -844,6 +844,11 @@ struct __declspec(dllexport) B {
 // M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_FB@pr26490@@QAEXXZ"
 }
 
+// dllexport trumps dllexport on an explicit instantiation.
+template <typename T> struct ExplicitInstantiationTwoAttributes { void f() {} };
+template struct __declspec(dllexport) __declspec(dllimport) ExplicitInstantiationTwoAttributes<int>;
+// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01?f@?$ExplicitInstantiationTwoAttributes@H@@QAEXXZ"
+
 
 //===----------------------------------------------------------------------===//
 // Classes with template base classes
@@ -958,14 +963,6 @@ template struct ExplicitInstantiationDeclTemplateBase<int>;
 // M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01?func@?$ExplicitInstantiationDeclTemplateBase@H@@QAEXXZ"
 // G32-DAG: define weak_odr x86_thiscallcc void @_ZN37ExplicitInstantiationDeclTemplateBaseIiE4funcEv
 
-template <typename T> struct ExplicitInstantiationDeclTemplateBase2 { void func() {} };
-extern template struct ExplicitInstantiationDeclTemplateBase2<int>;
-struct __declspec(dllexport) DerivedFromExplicitInstantiationDeclTemplateBase2 : public ExplicitInstantiationDeclTemplateBase2<int> {};
-template struct __declspec(dllimport) ExplicitInstantiationDeclTemplateBase2<int>;
-USEMEMFUNC(ExplicitInstantiationDeclTemplateBase2<int>, func)
-// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01?func@?$ExplicitInstantiationDeclTemplateBase2@H@@QAEXXZ"
-// G32-DAG: define weak_odr x86_thiscallcc void @_ZN38ExplicitInstantiationDeclTemplateBase2IiE4funcEv
-
 // PR26076
 struct LayerSelectionBound;
 template <typename> struct Selection {};
diff --git a/clang/test/CodeGenCXX/dllimport.cpp b/clang/test/CodeGenCXX/dllimport.cpp
index 021de44789a..629c2b6c8ba 100644
--- a/clang/test/CodeGenCXX/dllimport.cpp
+++ b/clang/test/CodeGenCXX/dllimport.cpp
@@ -656,7 +656,7 @@ namespace DontUseDtorAlias {
 
 namespace Vtordisp {
   // Don't dllimport the vtordisp.
-  // MO1-DAG: define linkonce_odr x86_thiscallcc void @"\01?f@?$C@D@Vtordisp@@$4PPPPPPPM@A@AEXXZ"
+  // MO1-DAG: define linkonce_odr x86_thiscallcc void @"\01?f@?$C@H@Vtordisp@@$4PPPPPPPM@A@AEXXZ"
 
   class Base {
     virtual void f() {}
@@ -667,7 +667,7 @@ namespace Vtordisp {
     C() {}
     virtual void f() {}
   };
-  template class C<char>;
+  USECLASS(C<int>);
 }
 
 namespace ClassTemplateStaticDef {
@@ -698,26 +698,31 @@ namespace PR19933 {
   template <typename T> struct A { static NonPOD x; };
   template <typename T> NonPOD A<T>::x;
   template struct __declspec(dllimport) A<int>;
-  // MSC-DAG: @"\01?x@?$A@H@PR19933@@2UNonPOD@2@A" = available_externally dllimport global %"struct.PR19933::NonPOD" zeroinitializer
+  USEVARTYPE(NonPOD, A<int>::x);
+  // MSC-DAG: @"\01?x@?$A@H@PR19933@@2UNonPOD@2@A" = external dllimport global %"struct.PR19933::NonPOD"
 
   int f();
   template <typename T> struct B { static int x; };
   template <typename T> int B<T>::x = f();
   template struct __declspec(dllimport) B<int>;
-  // MSC-DAG: @"\01?x@?$B@H@PR19933@@2HA" = available_externally dllimport global i32 0
+  USEVAR(B<int>::x);
+  // MSC-DAG: @"\01?x@?$B@H@PR19933@@2HA" = external dllimport global i32
 
   constexpr int g() { return 42; }
   template <typename T> struct C { static int x; };
   template <typename T> int C<T>::x = g();
   template struct __declspec(dllimport) C<int>;
-  // MSC-DAG: @"\01?x@?$C@H@PR19933@@2HA" = available_externally dllimport global i32 42
+  USEVAR(C<int>::x);
+  // MSC-DAG: @"\01?x@?$C@H@PR19933@@2HA" = external dllimport global i32
 
   template <int I> struct D { static int x, y; };
   template <int I> int D<I>::x = I + 1;
   template <int I> int D<I>::y = I + f();
   template struct __declspec(dllimport) D<42>;
-  // MSC-DAG: @"\01?x@?$D@$0CK@@PR19933@@2HA" = available_externally dllimport global i32 43
-  // MSC-DAG: @"\01?y@?$D@$0CK@@PR19933@@2HA" = available_externally dllimport global i32 0
+  USEVAR(D<42>::x);
+  USEVAR(D<42>::y);
+  // MSC-DAG: @"\01?x@?$D@$0CK@@PR19933@@2HA" = external dllimport global i32
+  // MSC-DAG: @"\01?y@?$D@$0CK@@PR19933@@2HA" = external dllimport global i32
 }
 
 namespace PR21355 {
@@ -805,6 +810,36 @@ template struct __declspec(dllimport) PR23770DerivedTemplate<int>;
 USEMEMFUNC(PR23770BaseTemplate<int>, f);
 // M32-DAG: declare dllimport x86_thiscallcc void @"\01?f@?$PR23770BaseTemplate@H@@QAEXXZ"
 
+namespace PR27810 {
+  template <class T>
+  struct basic_ostream {
+    struct sentry {
+      sentry() { }
+      void foo() { }
+    };
+  };
+  template class __declspec(dllimport) basic_ostream<char>;
+  // The explicit instantiation definition acts as an explicit instantiation
+  // *declaration*, dllimport is not inherited by the inner class, and no
+  // functions are emitted unless they are used.
+
+  USEMEMFUNC(basic_ostream<char>::sentry, foo);
+  // M32-DAG: define linkonce_odr x86_thiscallcc void @"\01?foo@sentry@?$basic_ostream@D@PR27810@@QAEXXZ"
+  // M32-NOT: ??0sentry@?$basic_ostream@D@PR27810@@QAE@XZ
+}
+
+namespace PR27811 {
+  template <class T> struct codecvt {
+    virtual ~codecvt() { }
+  };
+  template class __declspec(dllimport) codecvt<char>;
+
+  // dllimport means this explicit instantiation definition gets treated as a
+  // declaration. Thus, the vtable should not be marked used, and in fact
+  // nothing for this class should be emitted at all since it's not used.
+  // M32-NOT: codecvt
+}
+
 //===----------------------------------------------------------------------===//
 // Classes with template base classes
 //===----------------------------------------------------------------------===//
diff --git a/clang/test/CodeGenCXX/explicit-instantiation.cpp b/clang/test/CodeGenCXX/explicit-instantiation.cpp
index 6076444c25b..7e00d78e483 100644
--- a/clang/test/CodeGenCXX/explicit-instantiation.cpp
+++ b/clang/test/CodeGenCXX/explicit-instantiation.cpp
@@ -1,5 +1,6 @@
 // RUN: %clang_cc1 -emit-llvm -triple i686-pc-linux-gnu -std=c++1y -o - %s | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-NO-OPT
 // RUN: %clang_cc1 -emit-llvm -triple i686-pc-linux-gnu -std=c++1y -O3 -disable-llvm-optzns -o - %s | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-OPT
+// RUN: %clang_cc1 -emit-llvm -triple i686-pc-win32 -std=c++1y -o - %s | FileCheck %s --check-prefix=CHECK-MS
 
 // This check logically is attached to 'template int S<int>::i;' below.
 // CHECK: @_ZN1SIiE1iE = weak_odr global i32
@@ -103,6 +104,28 @@ int g() { return S<int>().f(); }
 template struct S<int>;
 }
 
+namespace NestedClasses {
+  // Check how explicit instantiation of an outer class affects the inner class.
+  template <typename T> struct Outer {
+    struct Inner {
+      void f() {}
+    };
+  };
+
+  // Explicit instantiation definition of Outer causes explicit instantiation
+  // definition of Inner.
+  template struct Outer<int>;
+  // CHECK: define weak_odr void @_ZN13NestedClasses5OuterIiE5Inner1fEv
+  // CHECK-MS: define weak_odr x86_thiscallcc void @"\01?f@Inner@?$Outer@H@NestedClasses@@QAEXXZ"
+
+  // Explicit instantiation declaration of Outer causes explicit instantiation
+  // declaration of Inner, but not in MSVC mode.
+  extern template struct Outer<char>;
+  auto use = &Outer<char>::Inner::f;
+  // CHECK: {{declare|define available_externally}} void @_ZN13NestedClasses5OuterIcE5Inner1fEv
+  // CHECK-MS: define linkonce_odr x86_thiscallcc void @"\01?f@Inner@?$Outer@D@NestedClasses@@QAEXXZ"
+}
+
 // Check that we emit definitions from explicit instantiations even when they
 // occur prior to the definition itself.
 template <typename T> struct S {
diff --git a/clang/test/SemaTemplate/extern-templates.cpp b/clang/test/SemaTemplate/extern-templates.cpp
index eca64ed595e..5eb9c9db127 100644
--- a/clang/test/SemaTemplate/extern-templates.cpp
+++ b/clang/test/SemaTemplate/extern-templates.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple i686-pc-win32 -fsyntax-only -verify %s -DMS
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu-pc-win32 -fsyntax-only -verify %s
 
 template<typename T>
 class X0 {
@@ -21,12 +22,20 @@ extern template class X0<int*>;
 
 template<typename T>
 void X0<T>::Inner::g(T t) {
-  t = 17; // expected-error{{incompatible}}
+#ifdef MS
+  t = 17; // expected-error{{assigning to 'long *' from incompatible}} expected-error{{assigning to 'int *' from incompatible}}
+#else
+  t = 17; // expected-error{{assigning to 'long *' from incompatible}}
+#endif
 }
 
 void test_intptr(X0<int*> xi, X0<int*>::Inner xii) {
   xi.f(0);
+#ifdef MS
+  xii.g(0); // expected-note {{instantiation}}
+#else
   xii.g(0);
+#endif
 }
 
 extern template class X0<long*>;