// RUN: %clang_cc1 -triple i686-windows-msvc   -fno-rtti -fno-threadsafe-statics -fms-extensions -emit-llvm -std=c++1y -O0 -o - %s -DMSABI -w | FileCheck --check-prefix=MSC --check-prefix=M32 %s
// RUN: %clang_cc1 -triple x86_64-windows-msvc -fno-rtti -fno-threadsafe-statics -fms-extensions -emit-llvm -std=c++1y -O0 -o - %s -DMSABI -w | FileCheck --check-prefix=MSC --check-prefix=M64 %s
// RUN: %clang_cc1 -triple i686-windows-gnu    -fno-rtti -fno-threadsafe-statics -fms-extensions -emit-llvm -std=c++1y -O0 -o - %s         -w | FileCheck --check-prefix=GNU --check-prefix=G32 %s
// RUN: %clang_cc1 -triple x86_64-windows-gnu  -fno-rtti -fno-threadsafe-statics -fms-extensions -emit-llvm -std=c++1y -O0 -o - %s         -w | FileCheck --check-prefix=GNU --check-prefix=G64 %s
// RUN: %clang_cc1 -triple i686-windows-msvc   -fno-rtti -fno-threadsafe-statics -fms-extensions -fms-compatibility-version=18.00 -emit-llvm -std=c++1y -O1 -disable-llvm-passes -o - %s -DMSABI -w | FileCheck --check-prefix=MO1 --check-prefix=M18 %s
// RUN: %clang_cc1 -triple i686-windows-msvc   -fno-rtti -fno-threadsafe-statics -fms-extensions -fms-compatibility-version=19.00 -emit-llvm -std=c++1y -O1 -disable-llvm-passes -o - %s -DMSABI -w | FileCheck --check-prefix=MO1 --check-prefix=M19 %s
// RUN: %clang_cc1 -triple i686-windows-gnu    -fno-rtti -fno-threadsafe-statics -fms-extensions -emit-llvm -std=c++1y -O1 -o - %s         -w | FileCheck --check-prefix=GO1 %s

// CHECK-NOT doesn't play nice with CHECK-DAG, so use separate run lines.
// RUN: %clang_cc1 -triple i686-windows-msvc   -fno-rtti -fno-threadsafe-statics -fms-extensions -emit-llvm -std=c++1y -O0 -o - %s -DMSABI -w | FileCheck --check-prefix=MSC2 %s
// RUN: %clang_cc1 -triple i686-windows-gnu    -fno-rtti -fno-threadsafe-statics -fms-extensions -emit-llvm -std=c++1y -O0 -o - %s         -w | FileCheck --check-prefix=GNU2 %s

// Helper structs to make templates more expressive.
struct ImplicitInst_Imported {};
struct ImplicitInst_NotImported {};
struct ExplicitDecl_Imported {};
struct ExplicitInst_Imported {};
struct ExplicitSpec_Imported {};
struct ExplicitSpec_Def_Imported {};
struct ExplicitSpec_InlineDef_Imported {};
struct ExplicitSpec_NotImported {};

#define JOIN2(x, y) x##y
#define JOIN(x, y) JOIN2(x, y)
#define UNIQ(name) JOIN(name, __LINE__)
#define USEVARTYPE(type, var) type UNIQ(use)() { return var; }
#define USEVAR(var) USEVARTYPE(int, var)
#define USE(func) void UNIQ(use)() { func(); }
#define USE1(func) void UNIQ(use)() { func(nullptr); }
#define USEMEMFUNC(class, func) void (class::*UNIQ(use)())() { return &class::func; }
#define USESTATICMEMFUNC(class, func) void (*UNIQ(use)())() { return &class::func; }
#define USECLASS(class) void UNIQ(USE)() { class x; }
#define USECOPYASSIGN(class) class& (class::*UNIQ(use)())(class&) { return &class::operator=; }
#define USEMOVEASSIGN(class) class& (class::*UNIQ(use)())(class&&) { return &class::operator=; }

//===----------------------------------------------------------------------===//
// Globals
//===----------------------------------------------------------------------===//

// Import declaration.
// MSC-DAG: @"?ExternGlobalDecl@@3HA" = external dllimport global i32
// GNU-DAG: @ExternGlobalDecl            = external dllimport global i32
__declspec(dllimport) extern int ExternGlobalDecl;
USEVAR(ExternGlobalDecl)

// dllimport implies a declaration.
// MSC-DAG: @"?GlobalDecl@@3HA" = external dllimport global i32
// GNU-DAG: @GlobalDecl            = external dllimport global i32
__declspec(dllimport) int GlobalDecl;
USEVAR(GlobalDecl)

// Redeclarations
// MSC-DAG: @"?GlobalRedecl1@@3HA" = external dllimport global i32
// GNU-DAG: @GlobalRedecl1            = external dllimport global i32
__declspec(dllimport) extern int GlobalRedecl1;
__declspec(dllimport) extern int GlobalRedecl1;
USEVAR(GlobalRedecl1)

// MSC-DAG: @"?GlobalRedecl2a@@3HA" = external dllimport global i32
// GNU-DAG: @GlobalRedecl2a            = external dllimport global i32
__declspec(dllimport) int GlobalRedecl2a;
__declspec(dllimport) int GlobalRedecl2a;
USEVAR(GlobalRedecl2a)

// M32-DAG: @"?GlobalRedecl2b@@3PAHA"   = external dllimport global i32*
// M64-DAG: @"?GlobalRedecl2b@@3PEAHEA" = external dllimport global i32*
// GNU-DAG: @GlobalRedecl2b                = external dllimport global i32*
int *__attribute__((dllimport)) GlobalRedecl2b;
int *__attribute__((dllimport)) GlobalRedecl2b;
USEVARTYPE(int*, GlobalRedecl2b)

// MSC-DAG: @"?GlobalRedecl2c@@3HA" = external dllimport global i32
// GNU-DAG: @GlobalRedecl2c            = external dllimport global i32
int GlobalRedecl2c __attribute__((dllimport));
int GlobalRedecl2c __attribute__((dllimport));
USEVAR(GlobalRedecl2c)

// NB: MSC issues a warning and makes GlobalRedecl3 dllexport. We follow GCC
// and drop the dllimport with a warning.
// MSC-DAG: @"?GlobalRedecl3@@3HA" = external dso_local global i32
// GNU-DAG: @GlobalRedecl3            = external global i32
__declspec(dllimport) extern int GlobalRedecl3;
                      extern int GlobalRedecl3; // dllimport ignored
USEVAR(GlobalRedecl3)

// MSC-DAG: @"?ExternalGlobal@ns@@3HA" = external dllimport global i32
// GNU-DAG: @_ZN2ns14ExternalGlobalE      = external dllimport global i32
namespace ns { __declspec(dllimport) int ExternalGlobal; }
USEVAR(ns::ExternalGlobal)

int __declspec(dllimport) f();
// MO1-DAG: @"?x@?1??inlineStaticLocalsFunc@@YAHXZ@4HA" = available_externally dllimport global i32 0
// MO1-DAG: @"??_B?1??inlineStaticLocalsFunc@@YAHXZ@51" = available_externally dllimport global i32 0
inline int __declspec(dllimport) inlineStaticLocalsFunc() {
  static int x = f();
  return x++;
};
USE(inlineStaticLocalsFunc);

// The address of a dllimport global cannot be used in constant initialization.
// M32-DAG: @"?arr@?1??initializationFunc@@YAPAHXZ@4QBQAHB" = internal global [1 x i32*] zeroinitializer
// GNU-DAG: @_ZZ18initializationFuncvE3arr = internal global [1 x i32*] zeroinitializer
int *initializationFunc() {
  static int *const arr[] = {&ExternGlobalDecl};
  return arr[0];
}
USE(initializationFunc);


//===----------------------------------------------------------------------===//
// Variable templates
//===----------------------------------------------------------------------===//

// Import declaration.
// MSC-DAG: @"??$ExternVarTmplDecl@UImplicitInst_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z17ExternVarTmplDeclI21ImplicitInst_ImportedE          = external dllimport global i32
template<typename T> __declspec(dllimport) extern int ExternVarTmplDecl;
USEVAR(ExternVarTmplDecl<ImplicitInst_Imported>)

// dllimport implies a declaration.
// MSC-DAG: @"??$VarTmplDecl@UImplicitInst_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z11VarTmplDeclI21ImplicitInst_ImportedE          = external dllimport global i32
template<typename T> __declspec(dllimport) int VarTmplDecl;
USEVAR(VarTmplDecl<ImplicitInst_Imported>)

// Redeclarations
// MSC-DAG: @"??$VarTmplRedecl1@UImplicitInst_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z14VarTmplRedecl1I21ImplicitInst_ImportedE          = external dllimport global i32
template<typename T> __declspec(dllimport) extern int VarTmplRedecl1;
template<typename T> __declspec(dllimport) extern int VarTmplRedecl1;
USEVAR(VarTmplRedecl1<ImplicitInst_Imported>)

// MSC-DAG: @"??$VarTmplRedecl2@UImplicitInst_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z14VarTmplRedecl2I21ImplicitInst_ImportedE          = external dllimport global i32
template<typename T> __declspec(dllimport) int VarTmplRedecl2;
template<typename T> __declspec(dllimport) int VarTmplRedecl2;
USEVAR(VarTmplRedecl2<ImplicitInst_Imported>)

// MSC-DAG: @"??$VarTmplRedecl3@UImplicitInst_Imported@@@@3HA" = external dso_local global i32
// GNU-DAG: @_Z14VarTmplRedecl3I21ImplicitInst_ImportedE          = external global i32
template<typename T> __declspec(dllimport) extern int VarTmplRedecl3;
template<typename T>                       extern int VarTmplRedecl3; // dllimport ignored
USEVAR(VarTmplRedecl3<ImplicitInst_Imported>)


// MSC-DAG: @"??$ExternalVarTmpl@UImplicitInst_Imported@@@ns@@3HA" = external dllimport global i32
// GNU-DAG: @_ZN2ns15ExternalVarTmplI21ImplicitInst_ImportedEE        = external dllimport global i32
namespace ns { template<typename T> __declspec(dllimport) int ExternalVarTmpl; }
USEVAR(ns::ExternalVarTmpl<ImplicitInst_Imported>)


template<typename T> int VarTmpl;
template<typename T> __declspec(dllimport) int ImportedVarTmpl;

// Import implicit instantiation of an imported variable template.
// MSC-DAG: @"??$ImportedVarTmpl@UImplicitInst_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z15ImportedVarTmplI21ImplicitInst_ImportedE          = external dllimport global i32
USEVAR(ImportedVarTmpl<ImplicitInst_Imported>)

// Import explicit instantiation declaration of an imported variable template.
// MSC-DAG: @"??$ImportedVarTmpl@UExplicitDecl_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z15ImportedVarTmplI21ExplicitDecl_ImportedE          = external dllimport global i32
extern template int ImportedVarTmpl<ExplicitDecl_Imported>;
USEVAR(ImportedVarTmpl<ExplicitDecl_Imported>)

// An explicit instantiation definition of an imported variable template cannot
// be imported because the template must be defined which is illegal.

// Import specialization of an imported variable template.
// MSC-DAG: @"??$ImportedVarTmpl@UExplicitSpec_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z15ImportedVarTmplI21ExplicitSpec_ImportedE          = external dllimport global i32
template<> __declspec(dllimport) int ImportedVarTmpl<ExplicitSpec_Imported>;
USEVAR(ImportedVarTmpl<ExplicitSpec_Imported>)

// Not importing specialization of an imported variable template without
// explicit dllimport.
// MSC-DAG: @"??$ImportedVarTmpl@UExplicitSpec_NotImported@@@@3HA" = dso_local global i32 0, align 4
// GNU-DAG: @_Z15ImportedVarTmplI24ExplicitSpec_NotImportedE          = dso_local global i32 0, align 4
template<> int ImportedVarTmpl<ExplicitSpec_NotImported>;
USEVAR(ImportedVarTmpl<ExplicitSpec_NotImported>)

// Import explicit instantiation declaration of a non-imported variable template.
// MSC-DAG: @"??$VarTmpl@UExplicitDecl_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z7VarTmplI21ExplicitDecl_ImportedE           = external dllimport global i32
extern template __declspec(dllimport) int VarTmpl<ExplicitDecl_Imported>;
USEVAR(VarTmpl<ExplicitDecl_Imported>)

// Import explicit instantiation definition of a non-imported variable template.
// MSC-DAG: @"??$VarTmpl@UExplicitInst_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z7VarTmplI21ExplicitInst_ImportedE           = external dllimport global i32
template __declspec(dllimport) int VarTmpl<ExplicitInst_Imported>;
USEVAR(VarTmpl<ExplicitInst_Imported>)

// Import specialization of a non-imported variable template.
// MSC-DAG: @"??$VarTmpl@UExplicitSpec_Imported@@@@3HA" = external dllimport global i32
// GNU-DAG: @_Z7VarTmplI21ExplicitSpec_ImportedE           = external dllimport global i32
template<> __declspec(dllimport) int VarTmpl<ExplicitSpec_Imported>;
USEVAR(VarTmpl<ExplicitSpec_Imported>)



//===----------------------------------------------------------------------===//
// Functions
//===----------------------------------------------------------------------===//

// GNU-DAG: declare dso_local void @_ZdlPv(i8*)

// Import function declaration.
// MSC-DAG: declare dllimport void @"?decl@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z4declv()
__declspec(dllimport) void decl();
USE(decl)

// extern "C"
// MSC-DAG: declare dllimport void @externC()
// GNU-DAG: declare dllimport void @externC()
extern "C" __declspec(dllimport) void externC();
USE(externC)

// Import inline function.
// MSC-DAG: declare dllimport void @"?inlineFunc@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z10inlineFuncv()
// MO1-DAG: define available_externally dllimport void @"?inlineFunc@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z10inlineFuncv()
__declspec(dllimport) inline void inlineFunc() {}
USE(inlineFunc)

// MSC-DAG: declare dllimport void @"?inlineDecl@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z10inlineDeclv()
// MO1-DAG: define available_externally dllimport void @"?inlineDecl@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z10inlineDeclv()
__declspec(dllimport) inline void inlineDecl();
                             void inlineDecl() {}
USE(inlineDecl)

// MSC-DAG: declare dllimport void @"?inlineDef@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z9inlineDefv()
// MO1-DAG: define available_externally dllimport void @"?inlineDef@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z9inlineDefv()
__declspec(dllimport) void inlineDef();
               inline void inlineDef() {}
USE(inlineDef)

// inline attributes
// MSC-DAG: declare dllimport void @"?noinline@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z8noinlinev()
__declspec(dllimport) __attribute__((noinline)) inline void noinline() {}
USE(noinline)

// MSC2-NOT: @"?alwaysInline@@YAXXZ"()
// GNU2-NOT: @_Z12alwaysInlinev()
__declspec(dllimport) __attribute__((always_inline)) inline void alwaysInline() {}
USE(alwaysInline)

// Redeclarations
// MSC-DAG: declare dllimport void @"?redecl1@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z7redecl1v()
__declspec(dllimport) void redecl1();
__declspec(dllimport) void redecl1();
USE(redecl1)

// NB: MSC issues a warning and makes redecl2/redecl3 dllexport. We follow GCC
// and drop the dllimport with a warning.
// MSC-DAG: declare dso_local void @"?redecl2@@YAXXZ"()
// GNU-DAG: declare dso_local void @_Z7redecl2v()
__declspec(dllimport) void redecl2();
                      void redecl2();
USE(redecl2)

// MSC-DAG: define dso_local dllexport void @"?redecl3@@YAXXZ"()
// GNU-DAG: define dso_local void @_Z7redecl3v()
__declspec(dllimport) void redecl3();
                      void redecl3() {} // dllimport ignored
USE(redecl3)


// Friend functions
// MSC-DAG: declare           dllimport void @"?friend1@@YAXXZ"()
// GNU-DAG: declare           dllimport void @_Z7friend1v()
// MSC-DAG: declare dso_local           void @"?friend2@@YAXXZ"()
// GNU-DAG: declare dso_local           void @_Z7friend2v()
// MSC-DAG: define  dso_local dllexport void @"?friend3@@YAXXZ"()
// GNU-DAG: define  dso_local           void @_Z7friend3v()
// MSC-DAG: declare dso_local           void @"?friend4@@YAXXZ"()
// GNU-DAG: declare dso_local           void @_Z7friend4v()
// MSC-DAG: declare           dllimport void @"?friend5@@YAXXZ"()
// GNU-DAG: declare           dllimport void @_Z7friend5v()

struct FuncFriend {
  friend __declspec(dllimport) void friend1();
  friend __declspec(dllimport) void friend2();
  friend __declspec(dllimport) void friend3();
};
__declspec(dllimport) void friend1();
                      void friend2(); // dllimport ignored
                      void friend3() {} // dllimport ignored

__declspec(dllimport) void friend4();
__declspec(dllimport) void friend5();
struct FuncFriendRedecl {
  friend void friend4(); // dllimport ignored
  friend void ::friend5();
};
USE(friend1)
USE(friend2)
USE(friend3)
USE(friend4)
USE(friend5)

// Implicit declarations can be redeclared with dllimport.
// MSC-DAG: declare dllimport noalias i8* @"??2@{{YAPAXI|YAPEAX_K}}@Z"(
// GNU-DAG: declare dllimport noalias i8* @_Znw{{[yj]}}(
__declspec(dllimport) void* operator new(__SIZE_TYPE__ n);
void UNIQ(use)() { ::operator new(42); }

// MSC-DAG: declare dllimport void @"?externalFunc@ns@@YAXXZ"()
// GNU-DAG: declare dllimport void @_ZN2ns12externalFuncEv()
namespace ns { __declspec(dllimport) void externalFunc(); }
USE(ns::externalFunc)

// A dllimport function referencing non-imported vars or functions must not be available_externally.

__declspec(dllimport) int ImportedVar;
int NonImportedVar;
__declspec(dllimport) int ImportedFunc();
int NonImportedFunc();
struct ClassWithNonImportedMethod { int f(); };

__declspec(dllimport) inline int ReferencingImportedVar() { return ImportedVar; }
// MO1-DAG: define available_externally dllimport i32 @"?ReferencingImportedVar@@YAHXZ"
__declspec(dllimport) inline int ReferencingNonImportedVar() { return NonImportedVar; }
// MO1-DAG: declare dllimport i32 @"?ReferencingNonImportedVar@@YAHXZ"()
__declspec(dllimport) inline int ReferencingImportedFunc() { return ImportedFunc(); }
// MO1-DAG: define available_externally dllimport i32 @"?ReferencingImportedFunc@@YAHXZ"
__declspec(dllimport) inline int ReferencingNonImportedFunc() { return NonImportedFunc(); }
// MO1-DAG: declare dllimport i32 @"?ReferencingNonImportedFunc@@YAHXZ"()
__declspec(dllimport) inline int ReferencingNonImportedMethod(ClassWithNonImportedMethod *x) { return x->f(); }
// MO1-DAG: declare dllimport i32 @"?ReferencingNonImportedMethod
__declspec(dllimport) inline int ReferencingClassMemberPtr(int (ClassWithNonImportedMethod::*p)(), ClassWithNonImportedMethod *x) { return (x->*p)(); }
// MO1-DAG: define available_externally dllimport i32 @"?ReferencingClassMemberPtr@@YAHP8ClassWithNonImportedMethod@@AEHXZPAU1@@Z"
USE(ReferencingImportedVar)
USE(ReferencingNonImportedVar)
USE(ReferencingImportedFunc)
USE(ReferencingNonImportedFunc)
USE1(ReferencingNonImportedMethod)
void UNIQ(use)() { ReferencingClassMemberPtr(&ClassWithNonImportedMethod::f, nullptr); }
// References to operator new and delete count too, despite not being DeclRefExprs.
__declspec(dllimport) inline int *ReferencingNonImportedNew() { return new int[2]; }
// MO1-DAG: declare dllimport i32* @"?ReferencingNonImportedNew@@YAPAHXZ"
__declspec(dllimport) inline int *ReferencingNonImportedDelete() { delete (int*)nullptr; }
// MO1-DAG: declare dllimport i32* @"?ReferencingNonImportedDelete@@YAPAHXZ"
USE(ReferencingNonImportedNew)
USE(ReferencingNonImportedDelete)
__declspec(dllimport) void* operator new[](__SIZE_TYPE__);
__declspec(dllimport) void operator delete(void*);
__declspec(dllimport) inline int *ReferencingImportedNew() { return new int[2]; }
// MO1-DAG: define available_externally dllimport i32* @"?ReferencingImportedNew@@YAPAHXZ"
__declspec(dllimport) inline int *ReferencingImportedDelete() { delete (int*)nullptr; }
// MO1-DAG: define available_externally dllimport i32* @"?ReferencingImportedDelete@@YAPAHXZ"
USE(ReferencingImportedNew)
USE(ReferencingImportedDelete)
struct ClassWithDtor { ~ClassWithDtor() {} };
struct __declspec(dllimport) ClassWithNonDllImportField { using X = ClassWithDtor; X t[2]; };
struct __declspec(dllimport) ClassWithNonDllImportBase : public ClassWithDtor { };
USECLASS(ClassWithNonDllImportField);
USECLASS(ClassWithNonDllImportBase);
// MO1-DAG: declare dllimport x86_thiscallcc void @"??1ClassWithNonDllImportBase@@QAE@XZ"(%struct.ClassWithNonDllImportBase*)
// MO1-DAG: declare dllimport x86_thiscallcc void @"??1ClassWithNonDllImportField@@QAE@XZ"(%struct.ClassWithNonDllImportField*)
struct ClassWithCtor { ClassWithCtor() {} };
struct __declspec(dllimport) ClassWithNonDllImportFieldWithCtor { ClassWithCtor t; };
USECLASS(ClassWithNonDllImportFieldWithCtor);
// MO1-DAG: declare dllimport x86_thiscallcc %struct.ClassWithNonDllImportFieldWithCtor* @"??0ClassWithNonDllImportFieldWithCtor@@QAE@XZ"(%struct.ClassWithNonDllImportFieldWithCtor* returned)
struct ClassWithImplicitDtor { __declspec(dllimport) ClassWithImplicitDtor(); ClassWithDtor member; };
__declspec(dllimport) inline void ReferencingDtorThroughDefinition() { ClassWithImplicitDtor x; };
USE(ReferencingDtorThroughDefinition)
// MO1-DAG: declare dllimport void @"?ReferencingDtorThroughDefinition@@YAXXZ"()
__declspec(dllimport) inline void ReferencingDtorThroughTemporary() { ClassWithImplicitDtor(); };
USE(ReferencingDtorThroughTemporary)
// MO1-DAG: declare dllimport void @"?ReferencingDtorThroughTemporary@@YAXXZ"()

// A dllimport function with a TLS variable must not be available_externally.
__declspec(dllimport) inline void FunctionWithTLSVar() { static __thread int x = 42; }
// MO1-DAG: declare dllimport void @"?FunctionWithTLSVar@@YAXXZ"
__declspec(dllimport) inline void FunctionWithNormalVar() { static int x = 42; }
// MO1-DAG: define available_externally dllimport void @"?FunctionWithNormalVar@@YAXXZ"
USE(FunctionWithTLSVar)
USE(FunctionWithNormalVar)


//===----------------------------------------------------------------------===//
// Function templates
//===----------------------------------------------------------------------===//

// Import function template declaration.
// MSC-DAG: declare dllimport void @"??$funcTmplDecl@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z12funcTmplDeclI21ImplicitInst_ImportedEvv()
template<typename T> __declspec(dllimport) void funcTmplDecl();
USE(funcTmplDecl<ImplicitInst_Imported>)

// Function template definitions cannot be imported.

// Import inline function template.
// MSC-DAG: declare dllimport void @"??$inlineFuncTmpl1@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z15inlineFuncTmpl1I21ImplicitInst_ImportedEvv()
// MO1-DAG: define available_externally dllimport void @"??$inlineFuncTmpl1@UImplicitInst_Imported@@@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z15inlineFuncTmpl1I21ImplicitInst_ImportedEvv()
template<typename T> __declspec(dllimport) inline void inlineFuncTmpl1() {}
USE(inlineFuncTmpl1<ImplicitInst_Imported>)

// MSC-DAG: declare dllimport void @"??$inlineFuncTmpl2@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z15inlineFuncTmpl2I21ImplicitInst_ImportedEvv()
// MO1-DAG: define available_externally dllimport void @"??$inlineFuncTmpl2@UImplicitInst_Imported@@@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z15inlineFuncTmpl2I21ImplicitInst_ImportedEvv()
template<typename T> inline void __attribute__((dllimport)) inlineFuncTmpl2() {}
USE(inlineFuncTmpl2<ImplicitInst_Imported>)

// MSC-DAG: define linkonce_odr dso_local void @"??$inlineFuncTmplDecl@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z18inlineFuncTmplDeclI21ImplicitInst_ImportedEvv()
// MO1-DAG: define linkonce_odr dso_local void @"??$inlineFuncTmplDecl@UImplicitInst_Imported@@@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z18inlineFuncTmplDeclI21ImplicitInst_ImportedEvv()
template<typename T> __declspec(dllimport) inline void inlineFuncTmplDecl();
template<typename T>                              void inlineFuncTmplDecl() {}
USE(inlineFuncTmplDecl<ImplicitInst_Imported>)

// MSC-DAG: define linkonce_odr dso_local void @"??$inlineFuncTmplDef@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z17inlineFuncTmplDefI21ImplicitInst_ImportedEvv()
// MO1-DAG: define linkonce_odr dso_local void @"??$inlineFuncTmplDef@UImplicitInst_Imported@@@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z17inlineFuncTmplDefI21ImplicitInst_ImportedEvv()
template<typename T> __declspec(dllimport) void inlineFuncTmplDef();
template<typename T>                inline void inlineFuncTmplDef() {}
USE(inlineFuncTmplDef<ImplicitInst_Imported>)


// Redeclarations
// MSC-DAG: declare dllimport void @"??$funcTmplRedecl1@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z15funcTmplRedecl1I21ImplicitInst_ImportedEvv()
template<typename T> __declspec(dllimport) void funcTmplRedecl1();
template<typename T> __declspec(dllimport) void funcTmplRedecl1();
USE(funcTmplRedecl1<ImplicitInst_Imported>)

// MSC-DAG: declare dso_local void @"??$funcTmplRedecl2@UImplicitInst_NotImported@@@@YAXXZ"()
// GNU-DAG: declare dso_local void @_Z15funcTmplRedecl2I24ImplicitInst_NotImportedEvv()
template<typename T> __declspec(dllimport) void funcTmplRedecl2();
template<typename T>                       void funcTmplRedecl2(); // dllimport ignored
USE(funcTmplRedecl2<ImplicitInst_NotImported>)

// MSC-DAG: define linkonce_odr dso_local void @"??$funcTmplRedecl3@UImplicitInst_NotImported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z15funcTmplRedecl3I24ImplicitInst_NotImportedEvv()
template<typename T> __declspec(dllimport) void funcTmplRedecl3();
template<typename T>                       void funcTmplRedecl3() {} // dllimport ignored
USE(funcTmplRedecl3<ImplicitInst_NotImported>)


// Function template friends
// MSC-DAG: declare dllimport   void @"??$funcTmplFriend1@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: declare dllimport   void @_Z15funcTmplFriend1I21ImplicitInst_ImportedEvv()
// MSC-DAG: declare             dso_local void @"??$funcTmplFriend2@UImplicitInst_NotImported@@@@YAXXZ"()
// GNU-DAG: declare             dso_local void @_Z15funcTmplFriend2I24ImplicitInst_NotImportedEvv()
// MSC-DAG: define linkonce_odr dso_local void @"??$funcTmplFriend3@UImplicitInst_NotImported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z15funcTmplFriend3I24ImplicitInst_NotImportedEvv()
// MSC-DAG: define linkonce_odr dso_local void @"??$funcTmplFriend4@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z15funcTmplFriend4I21ImplicitInst_ImportedEvv()
struct FuncTmplFriend {
  template<typename T> friend __declspec(dllimport) void funcTmplFriend1();
  template<typename T> friend __declspec(dllimport) void funcTmplFriend2();
  template<typename T> friend __declspec(dllimport) void funcTmplFriend3();
  template<typename T> friend __declspec(dllimport) inline void funcTmplFriend4();
};
template<typename T> __declspec(dllimport) void funcTmplFriend1();
template<typename T>                       void funcTmplFriend2(); // dllimport ignored
template<typename T>                       void funcTmplFriend3() {} // dllimport ignored
template<typename T>                       inline void funcTmplFriend4() {}
USE(funcTmplFriend1<ImplicitInst_Imported>)
USE(funcTmplFriend2<ImplicitInst_NotImported>)
USE(funcTmplFriend3<ImplicitInst_NotImported>)
USE(funcTmplFriend4<ImplicitInst_Imported>)

// MSC-DAG: declare dllimport void @"??$externalFuncTmpl@UImplicitInst_Imported@@@ns@@YAXXZ"()
// GNU-DAG: declare dllimport void @_ZN2ns16externalFuncTmplI21ImplicitInst_ImportedEEvv()
namespace ns { template<typename T> __declspec(dllimport) void externalFuncTmpl(); }
USE(ns::externalFuncTmpl<ImplicitInst_Imported>)


template<typename T> void funcTmpl() {}
template<typename T> inline void inlineFuncTmpl() {}
template<typename T> __declspec(dllimport) void importedFuncTmplDecl();
template<typename T> __declspec(dllimport) inline void importedFuncTmpl() {}

// Import implicit instantiation of an imported function template.
// MSC-DAG: declare dllimport void @"??$importedFuncTmplDecl@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z20importedFuncTmplDeclI21ImplicitInst_ImportedEvv()
USE(importedFuncTmplDecl<ImplicitInst_Imported>)

// MSC-DAG: declare dllimport void @"??$importedFuncTmpl@UImplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z16importedFuncTmplI21ImplicitInst_ImportedEvv()
// MO1-DAG: define available_externally dllimport void @"??$importedFuncTmpl@UImplicitInst_Imported@@@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z16importedFuncTmplI21ImplicitInst_ImportedEvv()
USE(importedFuncTmpl<ImplicitInst_Imported>)

// Import explicit instantiation declaration of an imported function template.
// MSC-DAG: declare dllimport void @"??$importedFuncTmpl@UExplicitDecl_Imported@@@@YAXXZ"()
// GNU-DAG: declare dso_local void @_Z16importedFuncTmplI21ExplicitDecl_ImportedEvv()
// MO1-DAG: define available_externally dllimport void @"??$importedFuncTmpl@UExplicitDecl_Imported@@@@YAXXZ"()
// GO1-DAG: define available_externally dso_local void @_Z16importedFuncTmplI21ExplicitDecl_ImportedEvv()
extern template void importedFuncTmpl<ExplicitDecl_Imported>();
USE(importedFuncTmpl<ExplicitDecl_Imported>)

// Import explicit instantiation definition of an imported function template.
// MSC-DAG: declare dllimport void @"??$importedFuncTmpl@UExplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: define weak_odr dso_local void @_Z16importedFuncTmplI21ExplicitInst_ImportedEvv()
// MO1-DAG: define available_externally dllimport void @"??$importedFuncTmpl@UExplicitInst_Imported@@@@YAXXZ"()
// GO1-DAG: define weak_odr dso_local void @_Z16importedFuncTmplI21ExplicitInst_ImportedEvv()
template void importedFuncTmpl<ExplicitInst_Imported>();
USE(importedFuncTmpl<ExplicitInst_Imported>)


// Import specialization of an imported function template.
// MSC-DAG: declare dllimport void @"??$importedFuncTmplDecl@UExplicitSpec_Imported@@@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z20importedFuncTmplDeclI21ExplicitSpec_ImportedEvv()
template<> __declspec(dllimport) void importedFuncTmplDecl<ExplicitSpec_Imported>();
USE(importedFuncTmplDecl<ExplicitSpec_Imported>)

// MSC-DAG-FIXME: declare dllimport void @"??$importedFuncTmplDecl@UExplicitSpec_Def_Imported@@@@YAXXZ"()
// MO1-DAG-FIXME: define available_externally dllimport void @"??$importedFuncTmplDecl@UExplicitSpec_Def_Imported@@@@YAXXZ"()
#ifdef MSABI
//template<> __declspec(dllimport) void importedFuncTmplDecl<ExplicitSpec_Def_Imported>() {}
//USE(importedFuncTmplDecl<ExplicitSpec_Def_Imported>)
#endif

// MSC-DAG: declare dllimport void @"??$importedFuncTmplDecl@UExplicitSpec_InlineDef_Imported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z20importedFuncTmplDeclI31ExplicitSpec_InlineDef_ImportedEvv()
// MO1-DAG: define available_externally dllimport void @"??$importedFuncTmplDecl@UExplicitSpec_InlineDef_Imported@@@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z20importedFuncTmplDeclI31ExplicitSpec_InlineDef_ImportedEvv()
template<> __declspec(dllimport) inline void importedFuncTmplDecl<ExplicitSpec_InlineDef_Imported>() {}
USE(importedFuncTmplDecl<ExplicitSpec_InlineDef_Imported>)


// MSC-DAG: declare dllimport void @"??$importedFuncTmpl@UExplicitSpec_Imported@@@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z16importedFuncTmplI21ExplicitSpec_ImportedEvv()
template<> __declspec(dllimport) void importedFuncTmpl<ExplicitSpec_Imported>();
USE(importedFuncTmpl<ExplicitSpec_Imported>)

// MSC-DAG-FIXME: declare dllimport void @"??$importedFuncTmpl@UExplicitSpec_Def_Imported@@@@YAXXZ"()
// MO1-DAG-FIXME: define available_externally dllimport void @"??$importedFuncTmpl@UExplicitSpec_Def_Imported@@@@YAXXZ"()
#ifdef MSABI
//template<> __declspec(dllimport) void importedFuncTmpl<ExplicitSpec_Def_Imported>() {}
//USE(importedFuncTmpl<ExplicitSpec_Def_Imported>)
#endif

// MSC-DAG: declare dllimport void @"??$importedFuncTmpl@UExplicitSpec_InlineDef_Imported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z16importedFuncTmplI31ExplicitSpec_InlineDef_ImportedEvv()
// MO1-DAG: define available_externally dllimport void @"??$importedFuncTmpl@UExplicitSpec_InlineDef_Imported@@@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z16importedFuncTmplI31ExplicitSpec_InlineDef_ImportedEvv()
template<> __declspec(dllimport) inline void importedFuncTmpl<ExplicitSpec_InlineDef_Imported>() {}
USE(importedFuncTmpl<ExplicitSpec_InlineDef_Imported>)


// Not importing specialization of an imported function template without
// explicit dllimport.
// MSC-DAG: define dso_local void @"??$importedFuncTmpl@UExplicitSpec_NotImported@@@@YAXXZ"()
// GNU-DAG: define dso_local void @_Z16importedFuncTmplI24ExplicitSpec_NotImportedEvv()
template<> void importedFuncTmpl<ExplicitSpec_NotImported>() {}
USE(importedFuncTmpl<ExplicitSpec_NotImported>)


// Import explicit instantiation declaration of a non-imported function template.
// MSC-DAG: declare dllimport void @"??$funcTmpl@UExplicitDecl_Imported@@@@YAXXZ"()
// MSC-DAG: declare dllimport void @"??$inlineFuncTmpl@UExplicitDecl_Imported@@@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z8funcTmplI21ExplicitDecl_ImportedEvv()
// GNU-DAG: declare dso_local void @_Z14inlineFuncTmplI21ExplicitDecl_ImportedEvv()
// MO1-DAG: define available_externally dllimport void @"??$inlineFuncTmpl@UExplicitDecl_Imported@@@@YAXXZ"()
// GO1-DAG: define available_externally dso_local void @_Z14inlineFuncTmplI21ExplicitDecl_ImportedEvv()
extern template __declspec(dllimport) void funcTmpl<ExplicitDecl_Imported>();
extern template __declspec(dllimport) void inlineFuncTmpl<ExplicitDecl_Imported>();
USE(funcTmpl<ExplicitDecl_Imported>)
USE(inlineFuncTmpl<ExplicitDecl_Imported>)


// Import explicit instantiation definition of a non-imported function template.
// MSC-DAG: declare dllimport void @"??$funcTmpl@UExplicitInst_Imported@@@@YAXXZ"()
// MSC-DAG: declare dllimport void @"??$inlineFuncTmpl@UExplicitInst_Imported@@@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z8funcTmplI21ExplicitInst_ImportedEvv()
// GNU-DAG: define weak_odr dso_local void @_Z14inlineFuncTmplI21ExplicitInst_ImportedEvv()
// MO1-DAG: declare dllimport void @"??$funcTmpl@UExplicitInst_Imported@@@@YAXXZ"()
// MO1-DAG: define available_externally dllimport void @"??$inlineFuncTmpl@UExplicitInst_Imported@@@@YAXXZ"()
// GO1-DAG: define available_externally dllimport void @_Z8funcTmplI21ExplicitInst_ImportedEvv()
// GO1-DAG: define weak_odr dso_local void @_Z14inlineFuncTmplI21ExplicitInst_ImportedEvv()
template __declspec(dllimport) void funcTmpl<ExplicitInst_Imported>();
template __declspec(dllimport) void inlineFuncTmpl<ExplicitInst_Imported>();
USE(funcTmpl<ExplicitInst_Imported>)
USE(inlineFuncTmpl<ExplicitInst_Imported>)


// Import specialization of a non-imported function template.
// MSC-DAG: declare dllimport void @"??$funcTmpl@UExplicitSpec_Imported@@@@YAXXZ"()
// GNU-DAG: declare dllimport void @_Z8funcTmplI21ExplicitSpec_ImportedEvv()
template<> __declspec(dllimport) void funcTmpl<ExplicitSpec_Imported>();
USE(funcTmpl<ExplicitSpec_Imported>)

// MSC-DAG-FIXME: declare dllimport void @"??$funcTmpl@UExplicitSpec_Def_Imported@@@@YAXXZ"()
// MO1-DAG-FIXME: define available_externally dllimport void @"??$funcTmpl@UExplicitSpec_Def_Imported@@@@YAXXZ"()
#ifdef MSABI
//template<> __declspec(dllimport) void funcTmpl<ExplicitSpec_Def_Imported>() {}
//USE(funcTmpl<ExplicitSpec_Def_Imported>)
#endif

// MSC-DAG: declare dllimport void @"??$funcTmpl@UExplicitSpec_InlineDef_Imported@@@@YAXXZ"()
// GNU-DAG: define linkonce_odr dso_local void @_Z8funcTmplI31ExplicitSpec_InlineDef_ImportedEvv()
// MO1-DAG: define available_externally dllimport void @"??$funcTmpl@UExplicitSpec_InlineDef_Imported@@@@YAXXZ"()
// GO1-DAG: define linkonce_odr dso_local void @_Z8funcTmplI31ExplicitSpec_InlineDef_ImportedEvv()
template<> __declspec(dllimport) inline void funcTmpl<ExplicitSpec_InlineDef_Imported>() {}
USE(funcTmpl<ExplicitSpec_InlineDef_Imported>)

#ifdef MSABI
namespace pr35435 {
struct X;
template <typename T> struct __declspec(dllimport) S {
  void foo(T *t) { t->problem(); }
};
template void S<X>::foo(X*); // Cannot be instantiated because X is incomplete; dllimport means it's treated as an instantiation decl.
}
#endif


//===----------------------------------------------------------------------===//
// Classes
//===----------------------------------------------------------------------===//

struct __declspec(dllimport) T {
  void a() {}
  // MO1-DAG: define available_externally dllimport x86_thiscallcc void @"?a@T@@QAEXXZ"

  static void StaticMethod();
  // MSC-DAG: declare dllimport void @"?StaticMethod@T@@SAXXZ"()
  // GNU-DAG: declare dllimport void @_ZN1T12StaticMethodEv()

  static int b;
  // MO1-DAG: @"?b@T@@2HA" = external dllimport global i32

  T& operator=(T&) = default;
  // MO1-DAG: define available_externally dllimport x86_thiscallcc dereferenceable({{[0-9]+}}) %struct.T* @"??4T@@QAEAAU0@AAU0@@Z"

  T& operator=(T&&) = default;
  // Note: Don't mark inline move operators dllimport because current MSVC versions don't export them.
  // M18-DAG: define linkonce_odr dso_local x86_thiscallcc dereferenceable({{[0-9]+}}) %struct.T* @"??4T@@QAEAAU0@$$QAU0@@Z"
  // M19-DAG: define available_externally dllimport x86_thiscallcc dereferenceable({{[0-9]+}}) %struct.T* @"??4T@@QAEAAU0@$$QAU0@@Z"
};
USEMEMFUNC(T, a)
USESTATICMEMFUNC(T, StaticMethod)
USEVAR(T::b)
USECOPYASSIGN(T)
USEMOVEASSIGN(T)

template <typename T> struct __declspec(dllimport) U { void foo() {} };
// MO1-DAG: define available_externally dllimport x86_thiscallcc void @"?foo@?$U@H@@QAEXXZ"
struct __declspec(dllimport) V : public U<int> { };
USEMEMFUNC(V, foo)

struct __declspec(dllimport) W { virtual void foo() {} };
USECLASS(W)
// vftable:
// MO1-DAG: @"??_SW@@6B@" = linkonce_odr unnamed_addr constant { [1 x i8*] } { [1 x i8*] [i8* bitcast (void (%struct.W*)* @"?foo@W@@UAEXXZ" to i8*)] }
// GO1-DAG: @_ZTV1W = available_externally dllimport unnamed_addr constant { [3 x i8*] } { [3 x i8*] [i8* null, i8* null, i8* bitcast (void (%struct.W*)* @_ZN1W3fooEv to i8*)] }

struct __declspec(dllimport) KeyFuncClass {
  constexpr KeyFuncClass() {}
  virtual void foo();
};
extern constexpr KeyFuncClass keyFuncClassVar = {};
// G32-DAG: @_ZTV12KeyFuncClass = external dllimport unnamed_addr constant { [3 x i8*] }

struct __declspec(dllimport) X : public virtual W {};
USECLASS(X)
// vbtable:
// MO1-DAG: @"??_8X@@7B@" = available_externally dllimport unnamed_addr constant [2 x i32] [i32 0, i32 4]

struct __declspec(dllimport) Y {
  int x;
};

struct __declspec(dllimport) Z { virtual ~Z() {} };
USECLASS(Z)
// User-defined dtor:
// MO1-DAG: define available_externally dllimport x86_thiscallcc void @"??1Z@@UAE@XZ"

namespace DontUseDtorAlias {
  struct __declspec(dllimport) A { ~A(); };
  struct __declspec(dllimport) B : A { ~B(); };
  inline A::~A() { }
  inline B::~B() { }
  // Emit a real definition of B's constructor; don't alias it to A's.
  // MO1-DAG: available_externally dllimport x86_thiscallcc void @"??1B@DontUseDtorAlias@@QAE@XZ"
  USECLASS(B)
}

namespace Vtordisp {
  // Don't dllimport the vtordisp.
  // MO1-DAG: define linkonce_odr dso_local x86_thiscallcc void @"?f@?$C@H@Vtordisp@@$4PPPPPPPM@A@AEXXZ"

  class __declspec(dllimport) Base {
    virtual void f() {}
  };
  template <typename T>
  class __declspec(dllimport) C : virtual public Base {
  public:
    C() {}
    virtual void f() {}
  };
  USECLASS(C<int>);
}

namespace ClassTemplateStaticDef {
  // Regular template static field:
  template <typename T> struct __declspec(dllimport) S {
    static int x;
  };
  template <typename T> int S<T>::x;
  // MSC-DAG: @"?x@?$S@H@ClassTemplateStaticDef@@2HA" = external dllimport global i32
  int f() { return S<int>::x; }

  // Partial class template specialization static field:
  template <typename A> struct T;
  template <typename A> struct __declspec(dllimport) T<A*> {
    static int x;
  };
  template <typename A> int T<A*>::x;
  // GNU-DAG: @_ZN22ClassTemplateStaticDef1TIPvE1xE = external dllimport global i32
  int g() { return T<void*>::x; }
}

namespace PR19933 {
// Don't dynamically initialize dllimport vars.
// MSC2-NOT: @llvm.global_ctors
// GNU2-NOT: @llvm.global_ctors

  struct NonPOD { NonPOD(); };
  template <typename T> struct A { static NonPOD x; };
  template <typename T> NonPOD A<T>::x;
  template struct __declspec(dllimport) A<int>;
  USEVARTYPE(NonPOD, A<int>::x);
  // MSC-DAG: @"?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>;
  USEVAR(B<int>::x);
  // MSC-DAG: @"?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>;
  USEVAR(C<int>::x);
  // MSC-DAG: @"?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>;
  USEVAR(D<42>::x);
  USEVAR(D<42>::y);
  // MSC-DAG: @"?x@?$D@$0CK@@PR19933@@2HA" = external dllimport global i32
  // MSC-DAG: @"?y@?$D@$0CK@@PR19933@@2HA" = external dllimport global i32
}

namespace PR21355 {
  struct __declspec(dllimport) S {
    virtual ~S();
  };
  S::~S() {}

  // S::~S is a key function, so we would ordinarily emit a strong definition for
  // the vtable. However, S is imported, so the vtable should be too.

  // GNU-DAG: @_ZTVN7PR213551SE = available_externally dllimport unnamed_addr constant { [4 x i8*] }
}

namespace PR21366 {
  struct __declspec(dllimport) S {
    void outOfLineMethod();
    void inlineMethod() {}
    inline void anotherInlineMethod();
    void outOfClassInlineMethod();
  };
  void S::anotherInlineMethod() {}
  inline void S::outOfClassInlineMethod() {}
}

namespace PR27319 {
  // Make sure we don't assert due to not having checked for operator delete on
  // the destructor.
  template <typename> struct A {
    virtual ~A() = default;
  };
  extern template struct __declspec(dllimport) A<int>;
  void f() { new A<int>(); }
  // MO1-DAG: @"??_S?$A@H@PR27319@@6B@" = linkonce_odr unnamed_addr constant { [1 x i8*] }
}

// MS ignores DLL attributes on partial specializations.
template <typename T> struct PartiallySpecializedClassTemplate {};
template <typename T> struct __declspec(dllimport) PartiallySpecializedClassTemplate<T*> { void f(); };
USEMEMFUNC(PartiallySpecializedClassTemplate<void*>, f);
// M32-DAG: declare dso_local x86_thiscallcc void @"?f@?$PartiallySpecializedClassTemplate@PAX@@QAEXXZ"
// G32-DAG: declare dllimport x86_thiscallcc void @_ZN33PartiallySpecializedClassTemplateIPvE1fEv

// Attributes on explicit specializations are honored.
template <typename T> struct ExplicitlySpecializedClassTemplate {};
template <> struct __declspec(dllimport) ExplicitlySpecializedClassTemplate<void*> { void f(); };
USEMEMFUNC(ExplicitlySpecializedClassTemplate<void*>, f);
// M32-DAG: declare dllimport x86_thiscallcc void @"?f@?$ExplicitlySpecializedClassTemplate@PAX@@QAEXXZ"
// G32-DAG: declare dllimport x86_thiscallcc void @_ZN34ExplicitlySpecializedClassTemplateIPvE1fEv

// MS inherits DLL attributes to partial specializations.
template <typename T> struct __declspec(dllimport) PartiallySpecializedImportedClassTemplate {};
template <typename T> struct PartiallySpecializedImportedClassTemplate<T*> { void f() {} };
USEMEMFUNC(PartiallySpecializedImportedClassTemplate<void*>, f);
// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc void @"?f@?$PartiallySpecializedImportedClassTemplate@PAX@@QAEXXZ"
// G32-DAG: define linkonce_odr dso_local x86_thiscallcc void @_ZN41PartiallySpecializedImportedClassTemplateIPvE1fEv

// Attributes on the instantiation take precedence over attributes on the template.
template <typename T> struct __declspec(dllexport) ExplicitlyInstantiatedWithDifferentAttr { void f() {} };
template struct __declspec(dllimport) ExplicitlyInstantiatedWithDifferentAttr<int>;
USEMEMFUNC(ExplicitlyInstantiatedWithDifferentAttr<int>, f);
// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc void @"?f@?$ExplicitlyInstantiatedWithDifferentAttr@H@@QAEXXZ"

template <typename T> struct ExplicitInstantiationDeclImportedDefTemplate { void f() {} ExplicitInstantiationDeclImportedDefTemplate() {}};
extern template struct ExplicitInstantiationDeclImportedDefTemplate<int>;
template struct __declspec(dllimport) ExplicitInstantiationDeclImportedDefTemplate<int>;
USECLASS(ExplicitInstantiationDeclImportedDefTemplate<int>);
USEMEMFUNC(ExplicitInstantiationDeclImportedDefTemplate<int>, f);
// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc void @"?f@?$ExplicitInstantiationDeclImportedDefTemplate@H@@QAEXXZ"
// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc %struct.ExplicitInstantiationDeclImportedDefTemplate* @"??0?$ExplicitInstantiationDeclImportedDefTemplate@H@@QAE@XZ"
// G32-DAG: define weak_odr dso_local x86_thiscallcc void @_ZN44ExplicitInstantiationDeclImportedDefTemplateIiE1fEv

template <typename T> struct __declspec(dllimport) ExplicitInstantiationDeclExportedDefImportedTemplate { void f() {} ExplicitInstantiationDeclExportedDefImportedTemplate() {} };
extern template struct __declspec(dllimport) ExplicitInstantiationDeclExportedDefImportedTemplate <int>;
template struct __declspec(dllexport) ExplicitInstantiationDeclExportedDefImportedTemplate<int>;
USECLASS(ExplicitInstantiationDeclExportedDefImportedTemplate<int>);
USEMEMFUNC(ExplicitInstantiationDeclExportedDefImportedTemplate<int>, f);
// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc void @"?f@?$ExplicitInstantiationDeclExportedDefImportedTemplate@H@@QAEXXZ"
// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc %struct.ExplicitInstantiationDeclExportedDefImportedTemplate* @"??0?$ExplicitInstantiationDeclExportedDefImportedTemplate@H@@QAE@XZ"

template <typename T> struct PR23770BaseTemplate { void f() {} };
template <typename T> struct PR23770DerivedTemplate : PR23770BaseTemplate<int> {};
extern template struct PR23770DerivedTemplate<int>;
template struct __declspec(dllimport) PR23770DerivedTemplate<int>;
USEMEMFUNC(PR23770BaseTemplate<int>, f);
// M32-DAG: declare dllimport x86_thiscallcc void @"?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 dso_local x86_thiscallcc void @"?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
//===----------------------------------------------------------------------===//

template <typename T> struct ClassTemplate { void func() {} };
template <typename T> struct __declspec(dllexport) ExportedClassTemplate { void func(); };
template <typename T> void ExportedClassTemplate<T>::func() {}
template <typename T> struct __declspec(dllimport) ImportedClassTemplate { void func(); };

template <typename T> struct ExplicitlySpecializedTemplate { void func() {} };
template <> struct ExplicitlySpecializedTemplate<int> { void func() {} };
template <typename T> struct ExplicitlyExportSpecializedTemplate { void func() {} };
template <> struct __declspec(dllexport) ExplicitlyExportSpecializedTemplate<int> { void func(); };
void ExplicitlyExportSpecializedTemplate<int>::func() {}
template <typename T> struct ExplicitlyImportSpecializedTemplate { void func() {} };
template <> struct __declspec(dllimport) ExplicitlyImportSpecializedTemplate<int> { void func(); };

template <typename T> struct ExplicitlyInstantiatedTemplate { void func() {} };
template struct ExplicitlyInstantiatedTemplate<int>;
template <typename T> struct ExplicitlyExportInstantiatedTemplate { void func(); };
template <typename T> void ExplicitlyExportInstantiatedTemplate<T>::func() {}
template struct __declspec(dllexport) ExplicitlyExportInstantiatedTemplate<int>;
template <typename T> struct ExplicitlyImportInstantiatedTemplate { void func(); };
template struct __declspec(dllimport) ExplicitlyImportInstantiatedTemplate<int>;


// MS: ClassTemplate<int> gets imported.
struct __declspec(dllimport) DerivedFromTemplate : public ClassTemplate<int> {};
USEMEMFUNC(ClassTemplate<int>, func)
// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc void @"?func@?$ClassTemplate@H@@QAEXXZ"
// G32-DAG: define linkonce_odr dso_local x86_thiscallcc void @_ZN13ClassTemplateIiE4funcEv

// ImportedTemplate is explicitly imported.
struct __declspec(dllimport) DerivedFromImportedTemplate : public ImportedClassTemplate<int> {};
USEMEMFUNC(ImportedClassTemplate<int>, func)
// M32-DAG: declare dllimport x86_thiscallcc void @"?func@?$ImportedClassTemplate@H@@QAEXXZ"
// G32-DAG: declare dllimport x86_thiscallcc void @_ZN21ImportedClassTemplateIiE4funcEv

// ExportedTemplate is explicitly exported.
struct __declspec(dllimport) DerivedFromExportedTemplate : public ExportedClassTemplate<int> {};
USEMEMFUNC(ExportedClassTemplate<int>, func)
// M32-DAG: define weak_odr dso_local dllexport x86_thiscallcc void @"?func@?$ExportedClassTemplate@H@@QAEXXZ"
// G32-DAG: define weak_odr dso_local dllexport x86_thiscallcc void @_ZN21ExportedClassTemplateIiE4funcEv

// Base class already implicitly instantiated without attribute.
struct DerivedFromTemplateD : public ClassTemplate<double> {};
struct __declspec(dllimport) DerivedFromTemplateD2 : public ClassTemplate<double> {};
USEMEMFUNC(ClassTemplate<double>, func)
// M32-DAG: declare dllimport x86_thiscallcc void @"?func@?$ClassTemplate@N@@QAEXXZ"
// G32-DAG: define linkonce_odr dso_local x86_thiscallcc void @_ZN13ClassTemplateIdE4funcEv

// MS: Base class already instantiated with dfferent attribute.
struct __declspec(dllexport) DerivedFromTemplateB : public ClassTemplate<bool> {};
struct __declspec(dllimport) DerivedFromTemplateB2 : public ClassTemplate<bool> {};
USEMEMFUNC(ClassTemplate<bool>, func)
// M32-DAG: define weak_odr dso_local dllexport x86_thiscallcc void @"?func@?$ClassTemplate@_N@@QAEXXZ"
// G32-DAG: define linkonce_odr dso_local x86_thiscallcc void @_ZN13ClassTemplateIbE4funcEv

// Base class already specialized without dll attribute.
struct __declspec(dllimport) DerivedFromExplicitlySpecializedTemplate : public ExplicitlySpecializedTemplate<int> {};
USEMEMFUNC(ExplicitlySpecializedTemplate<int>, func)
// M32-DAG: define linkonce_odr dso_local x86_thiscallcc void @"?func@?$ExplicitlySpecializedTemplate@H@@QAEXXZ"
// G32-DAG: define linkonce_odr dso_local x86_thiscallcc void @_ZN29ExplicitlySpecializedTemplateIiE4funcEv

// Base class alredy specialized with export attribute.
struct __declspec(dllimport) DerivedFromExplicitlyExportSpecializedTemplate : public ExplicitlyExportSpecializedTemplate<int> {};
USEMEMFUNC(ExplicitlyExportSpecializedTemplate<int>, func)
// M32-DAG: define dso_local dllexport x86_thiscallcc void @"?func@?$ExplicitlyExportSpecializedTemplate@H@@QAEXXZ"
// G32-DAG: define dso_local dllexport x86_thiscallcc void @_ZN35ExplicitlyExportSpecializedTemplateIiE4funcEv

// Base class already specialized with import attribute.
struct __declspec(dllimport) DerivedFromExplicitlyImportSpecializedTemplate : public ExplicitlyImportSpecializedTemplate<int> {};
USEMEMFUNC(ExplicitlyImportSpecializedTemplate<int>, func)
// M32-DAG: declare dllimport x86_thiscallcc void @"?func@?$ExplicitlyImportSpecializedTemplate@H@@QAEXXZ"
// G32-DAG: declare dllimport x86_thiscallcc void @_ZN35ExplicitlyImportSpecializedTemplateIiE4funcEv

// Base class already instantiated without dll attribute.
struct __declspec(dllimport) DerivedFromExplicitlyInstantiatedTemplate : public ExplicitlyInstantiatedTemplate<int> {};
USEMEMFUNC(ExplicitlyInstantiatedTemplate<int>, func)
// M32-DAG: define weak_odr dso_local x86_thiscallcc void @"?func@?$ExplicitlyInstantiatedTemplate@H@@QAEXXZ"
// G32-DAG: define weak_odr dso_local x86_thiscallcc void @_ZN30ExplicitlyInstantiatedTemplateIiE4funcEv

// Base class already instantiated with export attribute.
struct __declspec(dllimport) DerivedFromExplicitlyExportInstantiatedTemplate : public ExplicitlyExportInstantiatedTemplate<int> {};
USEMEMFUNC(ExplicitlyExportInstantiatedTemplate<int>, func)
// M32-DAG: define weak_odr dso_local dllexport x86_thiscallcc void @"?func@?$ExplicitlyExportInstantiatedTemplate@H@@QAEXXZ"
// G32-DAG: define weak_odr dso_local dllexport x86_thiscallcc void @_ZN36ExplicitlyExportInstantiatedTemplateIiE4funcEv

// Base class already instantiated with import attribute.
struct __declspec(dllimport) DerivedFromExplicitlyImportInstantiatedTemplate : public ExplicitlyImportInstantiatedTemplate<int> {};
USEMEMFUNC(ExplicitlyImportInstantiatedTemplate<int>, func)
// M32-DAG: declare dllimport x86_thiscallcc void @"?func@?$ExplicitlyImportInstantiatedTemplate@H@@QAEXXZ"
// G32-DAG: declare dllimport x86_thiscallcc void @_ZN36ExplicitlyImportInstantiatedTemplateIiE4funcEv

// MS: A dll attribute propagates through multiple levels of instantiation.
template <typename T> struct TopClass { void func() {} };
template <typename T> struct MiddleClass : public TopClass<T> { };
struct __declspec(dllimport) BottomClass : public MiddleClass<int> { };
USEMEMFUNC(TopClass<int>, func)
// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc void @"?func@?$TopClass@H@@QAEXXZ"
// G32-DAG: define linkonce_odr dso_local x86_thiscallcc void @_ZN8TopClassIiE4funcEv

template <typename T> struct ExplicitInstantiationDeclTemplateBase { void func() {} };
extern template struct ExplicitInstantiationDeclTemplateBase<int>;
struct __declspec(dllimport) DerivedFromExplicitInstantiationDeclTemplateBase : public ExplicitInstantiationDeclTemplateBase<int> {};
template struct ExplicitInstantiationDeclTemplateBase<int>;
USEMEMFUNC(ExplicitInstantiationDeclTemplateBase<int>, func)
// M32-DAG: declare dllimport x86_thiscallcc void @"?func@?$ExplicitInstantiationDeclTemplateBase@H@@QAEXXZ"
// G32-DAG: define weak_odr dso_local x86_thiscallcc void @_ZN37ExplicitInstantiationDeclTemplateBaseIiE4funcEv

template <typename T> struct ExplicitInstantiationDeclTemplateBase2 { void func() {} };
extern template struct ExplicitInstantiationDeclTemplateBase2<int>;
struct __declspec(dllimport) DerivedFromExplicitInstantiationDeclTemplateBase2 : public ExplicitInstantiationDeclTemplateBase2<int> {};
template struct __declspec(dllexport) ExplicitInstantiationDeclTemplateBase2<int>;
USEMEMFUNC(ExplicitInstantiationDeclTemplateBase2<int>, func)
// M32-DAG: declare dllimport x86_thiscallcc void @"?func@?$ExplicitInstantiationDeclTemplateBase2@H@@QAEXXZ"
// G32-DAG: define weak_odr dso_local x86_thiscallcc void @_ZN38ExplicitInstantiationDeclTemplateBase2IiE4funcEv

namespace pr39496 {
// Make sure dll attribute are inherited by static locals also in template
// specializations.
template <typename> struct __declspec(dllimport) S { int foo() { static int x; return x++; } };
int foo() { S<int> s; return s.foo(); }
// MO1-DAG: @"?x@?{{1|2}}??foo@?$S@H@pr39496@@Q{{[A-Z]*}}HXZ@4HA" = available_externally dllimport global i32 0, align 4

template <typename> struct T { int foo() { static int x; return x++; } };
extern template struct __declspec(dllimport) T<int>;
int bar() { T<int> t; return t.foo(); }
// MO1-DAG: @"?x@?{{1|2}}??foo@?$T@H@pr39496@@Q{{[A-Z]*}}HXZ@4HA" = available_externally dllimport global i32 0, align 4

template <typename T> struct __declspec(dllimport) U {
  void foo() {
    // Don't inherit dllimport to src before attaching the initializer.
    static constexpr char src[] = {"hello"};
    T arr[sizeof(src)];
  }
};
void baz() { U<int> u; u.foo(); } // No diagnostic.

}
