[MS] Consder constexpr globals to be inline, as in C++17

Summary:
Microsoft seems to do this regardless of the language mode, so we must
also do it in order to be ABI compatible.

Fixes PR36125

Reviewers: thakis

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D47956

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@371642 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index d87f7687670f67d1c00a49ed67949ebff6ccbc66..663674dd74a22f8af8810f644359dd9b47fec6f5 100644 (file)
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -6846,7 +6846,9 @@ NamedDecl *Sema::ActOnVariableDeclarator(
     // C++1z [dcl.spec.constexpr]p1:
     //   A static data member declared with the constexpr specifier is
     //   implicitly an inline variable.
-    if (NewVD->isStaticDataMember() && getLangOpts().CPlusPlus17)
+    if (NewVD->isStaticDataMember() &&
+        (getLangOpts().CPlusPlus17 ||
+         Context.getTargetInfo().getCXXABI().isMicrosoft()))
       NewVD->setImplicitlyInline();
     break;
 
@@ -12003,7 +12005,8 @@ void Sema::ActOnUninitializedDecl(Decl *RealDecl) {
       if (Var->isStaticDataMember()) {
         // C++1z removes the relevant rule; the in-class declaration is always
         // a definition there.
-        if (!getLangOpts().CPlusPlus17) {
+        if (!getLangOpts().CPlusPlus17 &&
+            !Context.getTargetInfo().getCXXABI().isMicrosoft()) {
           Diag(Var->getLocation(),
                diag::err_constexpr_static_mem_var_requires_init)
             << Var->getDeclName();

diff --git a/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p1.cpp b/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p1.cpp
index 5a4c5c9a9d63005bdaee2180b1b750a8ea303290..f472e9213fbedb67d13f37e30a5483477ca9dd55 100644 (file)
--- a/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p1.cpp
+++ b/test/CXX/dcl.dcl/dcl.spec/dcl.constexpr/p1.cpp
@@ -1,6 +1,10 @@
-// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s
-// RUN: %clang_cc1 -fsyntax-only -verify -std=c++14 %s
-// RUN: %clang_cc1 -fsyntax-only -verify -std=c++1z %s
+// RUN: %clang_cc1 -triple %itanium_abi_triple -fsyntax-only -verify -std=c++11 %s
+// RUN: %clang_cc1 -triple %itanium_abi_triple -fsyntax-only -verify -std=c++14 %s
+// RUN: %clang_cc1 -triple %itanium_abi_triple -fsyntax-only -verify -std=c++1z %s
+
+// MSVC always adopted the C++17 rule that implies that constexpr variables are
+// implicitly inline, so do the test again.
+// RUN: %clang_cc1 -triple x86_64-windows-msvc -DMS_ABI -fsyntax-only -verify -std=c++11 %s
 
 struct notlit { // expected-note {{not literal because}}
   notlit() {}
@@ -29,7 +33,7 @@ void f2(constexpr int i) {} // expected-error {{function parameter cannot be con
 struct s2 {
   constexpr int mi1; // expected-error {{non-static data member cannot be constexpr; did you intend to make it const?}}
   static constexpr int mi2;
-#if __cplusplus <= 201402L
+#if __cplusplus <= 201402L && !defined(MS_ABI)
   // expected-error@-2 {{requires an initializer}}
 #else
   // expected-error@-4 {{default initialization of an object of const}}

diff --git a/test/CXX/drs/dr7xx.cpp b/test/CXX/drs/dr7xx.cpp
index 30cc4b9abe9bf64cf24e57a31616c59052d68ec6..147560d3037b976afeb89f89307daed962caffc4 100644 (file)
--- a/test/CXX/drs/dr7xx.cpp
+++ b/test/CXX/drs/dr7xx.cpp
@@ -1,8 +1,8 @@
-// RUN: %clang_cc1 -std=c++98 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
-// RUN: %clang_cc1 -std=c++11 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
-// RUN: %clang_cc1 -std=c++14 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
-// RUN: %clang_cc1 -std=c++17 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
-// RUN: %clang_cc1 -std=c++2a %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++98 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++11 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++14 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++17 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++2a %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
 
 namespace dr705 { // dr705: yes
   namespace N {

diff --git a/test/CodeGenCXX/ms-constexpr-static-data-member.cpp b/test/CodeGenCXX/ms-constexpr-static-data-member.cpp
new file mode 100644 (file)
index 0000000..dc2c486
--- /dev/null
+++ b/test/CodeGenCXX/ms-constexpr-static-data-member.cpp
@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 -emit-llvm -triple=x86_64-windows-msvc %s -o - | FileCheck %s
+
+struct Foo { int x, y; };
+
+struct S {
+  // PR36125
+  static constexpr char sdm_char_array[] = "asdf";
+
+  // PR43280
+  static constexpr const char *sdm_char_ptr = "asdf";
+
+  static constexpr Foo sdm_udt{1, 2};
+};
+
+void useptr(const void *p);
+void usethem() {
+  useptr(&S::sdm_char_array);
+  useptr(&S::sdm_char_ptr);
+  useptr(&S::sdm_udt);
+}
+
+// CHECK-DAG: @"?sdm_char_array@S@@2QBDB" = linkonce_odr dso_local constant [5 x i8] c"asdf\00", comdat, align 1
+
+// CHECK-DAG: @"?sdm_char_ptr@S@@2QEBDEB" = linkonce_odr dso_local constant i8* getelementptr inbounds ([5 x i8], [5 x i8]* @"??_C@_04JIHMPGLA@asdf?$AA@", i32 0, i32 0), comdat, align 8
+
+// CHECK-DAG: @"?sdm_udt@S@@2UFoo@@B" = linkonce_odr dso_local constant %struct.Foo { i32 1, i32 2 }, comdat, align 4

diff --git a/test/CodeGenCXX/ms-integer-static-data-members-exported.cpp b/test/CodeGenCXX/ms-integer-static-data-members-exported.cpp
index 2537361383e6a46be5cd14a2152784bc3ed60d4b..d01b101037ed121dc22d4bc41027cb7e091fae74 100644 (file)
--- a/test/CodeGenCXX/ms-integer-static-data-members-exported.cpp
+++ b/test/CodeGenCXX/ms-integer-static-data-members-exported.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -emit-llvm -triple=i386-pc-win32 -fms-compatibility %s -o - | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm -triple=i386-pc-win32 -fms-extensions %s -o - | FileCheck %s
 
 enum Enum { zero, one, two };
 

diff --git a/test/CodeGenCXX/ms-integer-static-data-members.cpp b/test/CodeGenCXX/ms-integer-static-data-members.cpp
index 98414350b45199f2f243ee97cfa766a9649ce149..e48acbf06f740159cca53a6a05df2de398a69518 100644 (file)
--- a/test/CodeGenCXX/ms-integer-static-data-members.cpp
+++ b/test/CodeGenCXX/ms-integer-static-data-members.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 -emit-llvm -triple=i386-pc-win32 -fms-compatibility %s -o - | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm -triple=i386-pc-win32 %s -o - | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm -triple=x86_64-windows-msvc %s -o - | FileCheck %s
 
 struct S {
   static const int NoInit_Ref;

diff --git a/test/SemaCXX/cxx1y-variable-templates_in_class.cpp b/test/SemaCXX/cxx1y-variable-templates_in_class.cpp
index ecdd54f35fc3278ba43119d00e4cbdb10a9ff373..a16a5b54d8e0da411edcc11a62ae7d9a1443ae69 100644 (file)
--- a/test/SemaCXX/cxx1y-variable-templates_in_class.cpp
+++ b/test/SemaCXX/cxx1y-variable-templates_in_class.cpp
@@ -1,6 +1,6 @@
-// RUN: %clang_cc1 -std=c++98 -verify -fsyntax-only %s -Wno-c++11-extensions -Wno-c++1y-extensions -DPRECXX11
-// RUN: %clang_cc1 -std=c++11 -verify -fsyntax-only -Wno-c++1y-extensions %s
-// RUN: %clang_cc1 -std=c++1y -verify -fsyntax-only %s -DCPP1Y
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++98 -verify -fsyntax-only %s -Wno-c++11-extensions -Wno-c++1y-extensions -DPRECXX11
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++11 -verify -fsyntax-only -Wno-c++1y-extensions %s
+// RUN: %clang_cc1 -triple %itanium_abi_triple -std=c++1y -verify -fsyntax-only %s -DCPP1Y
 
 #define CONST const
 

diff --git a/test/SemaCXX/dllexport.cpp b/test/SemaCXX/dllexport.cpp
index e4a312adaeeadd6cff4ac5db2458949fd5f8ffb3..953684c73a584cb82f95a7b087627f5b294b09c8 100644 (file)
--- a/test/SemaCXX/dllexport.cpp
+++ b/test/SemaCXX/dllexport.cpp
@@ -742,7 +742,7 @@ struct MemberRedecl {
 
   static         int  StaticField;         // expected-note{{previous declaration is here}}
   static  const  int  StaticConstField;    // expected-note{{previous declaration is here}}
-  constexpr static int ConstexprField = 1; // expected-note{{previous declaration is here}}
+  constexpr static int ConstexprField = 1; // expected-note-re{{previous {{(declaration|definition)}} is here}}
 };
 
 __declspec(dllexport)        void MemberRedecl::normalDef() {}         // expected-error{{redeclaration of 'MemberRedecl::normalDef' cannot add 'dllexport' attribute}}
@@ -757,7 +757,12 @@ __declspec(dllexport)        void MemberRedecl::staticInlineDecl() {}  // expect
 
 __declspec(dllexport)        int  MemberRedecl::StaticField = 1;       // expected-error{{redeclaration of 'MemberRedecl::StaticField' cannot add 'dllexport' attribute}}
 __declspec(dllexport) const  int  MemberRedecl::StaticConstField = 1;  // expected-error{{redeclaration of 'MemberRedecl::StaticConstField' cannot add 'dllexport' attribute}}
-__declspec(dllexport) constexpr int MemberRedecl::ConstexprField;      // expected-error{{redeclaration of 'MemberRedecl::ConstexprField' cannot add 'dllexport' attribute}}
+#ifdef MS
+// expected-warning@+4{{attribute declaration must precede definition}}
+#else
+// expected-error@+2{{redeclaration of 'MemberRedecl::ConstexprField' cannot add 'dllexport' attribute}}
+#endif
+__declspec(dllexport) constexpr int MemberRedecl::ConstexprField;
 
 #ifdef MS
 struct __declspec(dllexport) ClassWithMultipleDefaultCtors {
@@ -841,7 +846,7 @@ struct MemTmplRedecl {
 #if __has_feature(cxx_variable_templates)
   template<typename T> static        int  StaticField;         // expected-note{{previous declaration is here}}
   template<typename T> static const  int  StaticConstField;    // expected-note{{previous declaration is here}}
-  template<typename T> constexpr static int ConstexprField = 1; // expected-note{{previous declaration is here}}
+  template<typename T> constexpr static int ConstexprField = 1; // expected-note-re{{previous {{(declaration|definition)}} is here}}
 #endif // __has_feature(cxx_variable_templates)
 };
 
@@ -855,7 +860,13 @@ template<typename T> __declspec(dllexport)        void MemTmplRedecl::staticInli
 #if __has_feature(cxx_variable_templates)
 template<typename T> __declspec(dllexport)        int  MemTmplRedecl::StaticField = 1;      // expected-error{{redeclaration of 'MemTmplRedecl::StaticField' cannot add 'dllexport' attribute}}
 template<typename T> __declspec(dllexport) const  int  MemTmplRedecl::StaticConstField = 1; // expected-error{{redeclaration of 'MemTmplRedecl::StaticConstField' cannot add 'dllexport' attribute}}
-template<typename T> __declspec(dllexport) constexpr int MemTmplRedecl::ConstexprField;     // expected-error{{redeclaration of 'MemTmplRedecl::ConstexprField' cannot add 'dllexport' attribute}}
+
+#ifdef MS
+// expected-warning@+4{{attribute declaration must precede definition}}
+#else
+// expected-error@+2{{redeclaration of 'MemTmplRedecl::ConstexprField' cannot add 'dllexport' attribute}}
+#endif
+template<typename T> __declspec(dllexport) constexpr int MemTmplRedecl::ConstexprField;
 #endif // __has_feature(cxx_variable_templates)
 
 
@@ -1045,7 +1056,7 @@ struct CTMR /*ClassTmplMemberRedecl*/ {
 
   static         int  StaticField;         // expected-note{{previous declaration is here}}
   static  const  int  StaticConstField;    // expected-note{{previous declaration is here}}
-  constexpr static int ConstexprField = 1; // expected-note{{previous declaration is here}}
+  constexpr static int ConstexprField = 1; // expected-note-re{{previous {{(definition|declaration)}} is here}}
 };
 
 template<typename T> __declspec(dllexport)        void CTMR<T>::normalDef() {}         // expected-error{{redeclaration of 'CTMR::normalDef' cannot add 'dllexport' attribute}}
@@ -1060,7 +1071,12 @@ template<typename T> __declspec(dllexport)        void CTMR<T>::staticInlineDecl
 
 template<typename T> __declspec(dllexport)        int  CTMR<T>::StaticField = 1;       // expected-error{{redeclaration of 'CTMR::StaticField' cannot add 'dllexport' attribute}}
 template<typename T> __declspec(dllexport) const  int  CTMR<T>::StaticConstField = 1;  // expected-error{{redeclaration of 'CTMR::StaticConstField' cannot add 'dllexport' attribute}}
-template<typename T> __declspec(dllexport) constexpr int CTMR<T>::ConstexprField;      // expected-error{{redeclaration of 'CTMR::ConstexprField' cannot add 'dllexport' attribute}}
+#ifdef MS
+// expected-warning@+4{{attribute declaration must precede definition}}
+#else
+// expected-error@+2{{redeclaration of 'CTMR::ConstexprField' cannot add 'dllexport' attribute}}
+#endif
+template<typename T> __declspec(dllexport) constexpr int CTMR<T>::ConstexprField;
 
 
 
@@ -1120,7 +1136,7 @@ struct CTMTR /*ClassTmplMemberTmplRedecl*/ {
 #if __has_feature(cxx_variable_templates)
   template<typename U> static        int  StaticField;         // expected-note{{previous declaration is here}}
   template<typename U> static const  int  StaticConstField;    // expected-note{{previous declaration is here}}
-  template<typename U> constexpr static int ConstexprField = 1; // expected-note{{previous declaration is here}}
+  template<typename U> constexpr static int ConstexprField = 1; // expected-note-re{{previous {{(declaration|definition)}} is here}}
 #endif // __has_feature(cxx_variable_templates)
 };
 
@@ -1134,7 +1150,12 @@ template<typename T> template<typename U> __declspec(dllexport)        void CTMT
 #if __has_feature(cxx_variable_templates)
 template<typename T> template<typename U> __declspec(dllexport)        int  CTMTR<T>::StaticField = 1;       // expected-error{{redeclaration of 'CTMTR::StaticField' cannot add 'dllexport' attribute}}
 template<typename T> template<typename U> __declspec(dllexport) const  int  CTMTR<T>::StaticConstField = 1;  // expected-error{{redeclaration of 'CTMTR::StaticConstField' cannot add 'dllexport' attribute}}
-template<typename T> template<typename U> __declspec(dllexport) constexpr int CTMTR<T>::ConstexprField;      // expected-error{{redeclaration of 'CTMTR::ConstexprField' cannot add 'dllexport' attribute}}
+#ifdef MS
+// expected-warning@+4{{attribute declaration must precede definition}}
+#else
+// expected-error@+2{{redeclaration of 'CTMTR::ConstexprField' cannot add 'dllexport' attribute}}
+#endif
+template<typename T> template<typename U> __declspec(dllexport) constexpr int CTMTR<T>::ConstexprField;
 #endif // __has_feature(cxx_variable_templates)
 
 // FIXME: Precedence rules seem to be different for classes.

diff --git a/test/SemaCXX/dllimport.cpp b/test/SemaCXX/dllimport.cpp
index 73aea57ba2be79d4cd9c40d6fbc72d52108e5b8b..80c6f2e678586a5749870b74dc1177b4a2aa41fe 100644 (file)
--- a/test/SemaCXX/dllimport.cpp
+++ b/test/SemaCXX/dllimport.cpp
@@ -2,6 +2,7 @@
 // RUN: %clang_cc1 -triple x86_64-win32   -fsyntax-only -fms-extensions -verify -std=c++1y -Wunsupported-dll-base-class-template -DMS %s
 // RUN: %clang_cc1 -triple i686-mingw32   -fsyntax-only -fms-extensions -verify -std=c++1y -Wunsupported-dll-base-class-template -DGNU %s
 // RUN: %clang_cc1 -triple x86_64-mingw32 -fsyntax-only -fms-extensions -verify -std=c++11 -Wunsupported-dll-base-class-template -DGNU %s
+// RUN: %clang_cc1 -triple x86_64-mingw32 -fsyntax-only -fms-extensions -verify -std=c++17 -Wunsupported-dll-base-class-template -DGNU %s
 
 // Helper structs to make templates more expressive.
 struct ImplicitInst_Imported {};
@@ -586,7 +587,10 @@ public:
   __declspec(dllimport) static  const  int  StaticConstFieldEqualInit = 1;
   __declspec(dllimport) static  const  int  StaticConstFieldBraceInit{1};
   __declspec(dllimport) constexpr static int ConstexprField = 1;
-  __declspec(dllimport) constexpr static int ConstexprFieldDef = 1; // expected-note{{attribute is here}}
+#if __cplusplus < 201703L && !defined(MS)
+  // expected-note@+2{{attribute is here}}
+#endif
+  __declspec(dllimport) constexpr static int ConstexprFieldDef = 1;
 };
 
 #ifdef MS
@@ -631,7 +635,10 @@ inline void ImportMembers::staticInlineDef() {}
 
        int  ImportMembers::StaticFieldDef; // expected-error{{definition of dllimport static field not allowed}}
 const  int  ImportMembers::StaticConstFieldDef = 1; // expected-error{{definition of dllimport static field not allowed}}
-constexpr int ImportMembers::ConstexprFieldDef; // expected-error{{definition of dllimport static field not allowed}}
+#if __cplusplus < 201703L && !defined(MS)
+// expected-error@+2{{definition of dllimport static field not allowed}}
+#endif
+constexpr int ImportMembers::ConstexprFieldDef;
 
 
 // Import on member definitions.
@@ -667,7 +674,11 @@ __declspec(dllimport)        void ImportMemberDefs::staticInlineDecl() {}
 
 __declspec(dllimport)        int  ImportMemberDefs::StaticField; // expected-error{{definition of dllimport static field not allowed}} expected-note{{attribute is here}}
 __declspec(dllimport) const  int  ImportMemberDefs::StaticConstField = 1; // expected-error{{definition of dllimport static field not allowed}} expected-note{{attribute is here}}
-__declspec(dllimport) constexpr int ImportMemberDefs::ConstexprField; // expected-error{{definition of dllimport static field not allowed}} expected-note{{attribute is here}}
+#if __cplusplus < 201703L && !defined(MS)
+// expected-error@+3{{definition of dllimport static field not allowed}}
+// expected-note@+2{{attribute is here}}
+#endif
+__declspec(dllimport) constexpr int ImportMemberDefs::ConstexprField;
 
 
 // Import special member functions.
@@ -800,7 +811,7 @@ struct MemberRedecl {
 
   static         int  StaticField;         // expected-note{{previous declaration is here}}
   static  const  int  StaticConstField;    // expected-note{{previous declaration is here}}
-  constexpr static int ConstexprField = 1; // expected-note{{previous declaration is here}}
+  constexpr static int ConstexprField = 1; // expected-note-re{{previous {{(declaration|definition)}} is here}}
 };
 
 __declspec(dllimport)        void MemberRedecl::normalDef() {}         // expected-error{{redeclaration of 'MemberRedecl::normalDef' cannot add 'dllimport' attribute}}
@@ -831,9 +842,15 @@ __declspec(dllimport)        int  MemberRedecl::StaticField = 1;       // expect
 __declspec(dllimport) const  int  MemberRedecl::StaticConstField = 1;  // expected-error{{redeclaration of 'MemberRedecl::StaticConstField' cannot add 'dllimport' attribute}}
                                                                        // expected-error@-1{{definition of dllimport static field not allowed}}
                                                                        // expected-note@-2{{attribute is here}}
-__declspec(dllimport) constexpr int MemberRedecl::ConstexprField;      // expected-error{{redeclaration of 'MemberRedecl::ConstexprField' cannot add 'dllimport' attribute}}
-                                                                       // expected-error@-1{{definition of dllimport static field not allowed}}
-                                                                       // expected-note@-2{{attribute is here}}
+
+#if __cplusplus < 201703L && !defined(MS)
+// expected-error@+6{{redeclaration of 'MemberRedecl::ConstexprField' cannot add 'dllimport' attribute}}
+// expected-error@+5{{definition of dllimport static field not allowed}}
+// expected-note@+4{{attribute is here}}
+#else
+// expected-warning@+2{{attribute declaration must precede definition}}
+#endif
+__declspec(dllimport) constexpr int MemberRedecl::ConstexprField;
 
 
 
@@ -875,7 +892,7 @@ struct ImportMemberTmpl {
   template<typename T> __declspec(dllimport) static const  int  StaticConstFieldEqualInit = 1;
   template<typename T> __declspec(dllimport) static const  int  StaticConstFieldBraceInit{1};
   template<typename T> __declspec(dllimport) constexpr static int ConstexprField = 1;
-  template<typename T> __declspec(dllimport) constexpr static int ConstexprFieldDef = 1; // expected-note{{attribute is here}}
+  template<typename T> __declspec(dllimport) constexpr static int ConstexprFieldDef = 1;
 #endif // __has_feature(cxx_variable_templates)
 };
 
@@ -900,7 +917,9 @@ template<typename T> inline void ImportMemberTmpl::staticInlineDef() {} // expec
 #if __has_feature(cxx_variable_templates)
 template<typename T>        int  ImportMemberTmpl::StaticFieldDef; // expected-error{{definition of dllimport static field not allowed}}
 template<typename T> const  int  ImportMemberTmpl::StaticConstFieldDef = 1; // expected-error{{definition of dllimport static field not allowed}}
-template<typename T> constexpr int ImportMemberTmpl::ConstexprFieldDef; // expected-error{{definition of dllimport static field not allowed}}
+#ifdef MS
+template<typename T> constexpr int ImportMemberTmpl::ConstexprFieldDef;
+#endif
 #endif // __has_feature(cxx_variable_templates)
 
 
@@ -921,7 +940,9 @@ struct MemTmplRedecl {
 #if __has_feature(cxx_variable_templates)
   template<typename T> static        int  StaticField;         // expected-note{{previous declaration is here}}
   template<typename T> static const  int  StaticConstField;    // expected-note{{previous declaration is here}}
-  template<typename T> constexpr static int ConstexprField = 1; // expected-note{{previous declaration is here}}
+#ifdef MS
+  template<typename T> constexpr static int ConstexprField = 1; // expected-note{{previous definition is here}}
+#endif
 #endif // __has_feature(cxx_variable_templates)
 };
 
@@ -949,9 +970,10 @@ template<typename T> __declspec(dllimport)        int  MemTmplRedecl::StaticFiel
 template<typename T> __declspec(dllimport) const  int  MemTmplRedecl::StaticConstField = 1; // expected-error{{redeclaration of 'MemTmplRedecl::StaticConstField' cannot add 'dllimport' attribute}}
                                                                                             // expected-error@-1{{definition of dllimport static field not allowed}}
                                                                                             // expected-note@-2{{attribute is here}}
-template<typename T> __declspec(dllimport) constexpr int MemTmplRedecl::ConstexprField;     // expected-error{{redeclaration of 'MemTmplRedecl::ConstexprField' cannot add 'dllimport' attribute}}
-                                                                                            // expected-error@-1{{definition of dllimport static field not allowed}}
-                                                                                            // expected-note@-2{{attribute is here}}
+#ifdef MS
+// expected-warning@+1{{attribute declaration must precede definition}}
+template<typename T> __declspec(dllimport) constexpr int MemTmplRedecl::ConstexprField;
+#endif
 #endif // __has_feature(cxx_variable_templates)
 
 
@@ -1159,7 +1181,10 @@ public:
   __declspec(dllimport) static  const  int  StaticConstFieldEqualInit = 1;
   __declspec(dllimport) static  const  int  StaticConstFieldBraceInit{1};
   __declspec(dllimport) constexpr static int ConstexprField = 1;
-  __declspec(dllimport) constexpr static int ConstexprFieldDef = 1; // expected-note{{attribute is here}}
+#if __cplusplus < 201703L && !defined(MS)
+  // expected-note@+2{{attribute is here}}
+#endif
+  __declspec(dllimport) constexpr static int ConstexprFieldDef = 1;
 };
 
 // NB: MSVC is inconsistent here and disallows *InlineDef on class templates,
@@ -1203,7 +1228,10 @@ template<typename T>        void ImportClassTmplMembers<T>::staticInlineDecl() {
 
 template<typename T>        int  ImportClassTmplMembers<T>::StaticFieldDef; // expected-warning{{definition of dllimport static field}}
 template<typename T> const  int  ImportClassTmplMembers<T>::StaticConstFieldDef = 1; // expected-warning{{definition of dllimport static field}}
-template<typename T> constexpr int ImportClassTmplMembers<T>::ConstexprFieldDef; // expected-warning{{definition of dllimport static field}}
+#if __cplusplus < 201703L && !defined(MS)
+// expected-warning@+2{{definition of dllimport static field}}
+#endif
+template<typename T> constexpr int ImportClassTmplMembers<T>::ConstexprFieldDef;
 
 
 // Redeclarations cannot add dllimport.
@@ -1227,7 +1255,7 @@ struct CTMR /*ClassTmplMemberRedecl*/ {
 
   static         int  StaticField;         // expected-note{{previous declaration is here}}
   static  const  int  StaticConstField;    // expected-note{{previous declaration is here}}
-  constexpr static int ConstexprField = 1; // expected-note{{previous declaration is here}}
+  constexpr static int ConstexprField = 1; // expected-note-re{{previous {{(declaration|definition)}} is here}}
 };
 
 template<typename T> __declspec(dllimport)        void CTMR<T>::normalDef() {}         // expected-error{{redeclaration of 'CTMR::normalDef' cannot add 'dllimport' attribute}}
@@ -1256,9 +1284,15 @@ template<typename T> __declspec(dllimport)        int  CTMR<T>::StaticField = 1;
 template<typename T> __declspec(dllimport) const  int  CTMR<T>::StaticConstField = 1;  // expected-error{{redeclaration of 'CTMR::StaticConstField' cannot add 'dllimport' attribute}}
                                                                                        // expected-warning@-1{{definition of dllimport static field}}
                                                                                        // expected-note@-2{{attribute is here}}
-template<typename T> __declspec(dllimport) constexpr int CTMR<T>::ConstexprField;      // expected-error{{redeclaration of 'CTMR::ConstexprField' cannot add 'dllimport' attribute}}
-                                                                                       // expected-warning@-1{{definition of dllimport static field}}
-                                                                                       // expected-note@-2{{attribute is here}}
+
+#if __cplusplus < 201703L && !defined(MS)
+// expected-error@+6{{redeclaration of 'CTMR::ConstexprField' cannot add 'dllimport' attribute}}
+// expected-warning@+5{{definition of dllimport static field}}
+// expected-note@+4{{attribute is here}}
+#else
+// expected-warning@+2{{attribute declaration must precede definition}}
+#endif
+template<typename T> __declspec(dllimport) constexpr int CTMR<T>::ConstexprField;
 
 
 
@@ -1306,7 +1340,9 @@ struct ImportClsTmplMemTmpl {
   template<typename U> __declspec(dllimport) static const  int  StaticConstFieldEqualInit = 1;
   template<typename U> __declspec(dllimport) static const  int  StaticConstFieldBraceInit{1};
   template<typename U> __declspec(dllimport) constexpr static int ConstexprField = 1;
-  template<typename U> __declspec(dllimport) constexpr static int ConstexprFieldDef = 1; // expected-note{{attribute is here}}
+#ifdef MS
+  template<typename U> __declspec(dllimport) constexpr static int ConstexprFieldDef = 1;
+#endif
 #endif // __has_feature(cxx_variable_templates)
 };
 
@@ -1331,7 +1367,9 @@ template<typename T> template<typename U> inline void ImportClsTmplMemTmpl<T>::s
 #if __has_feature(cxx_variable_templates)
 template<typename T> template<typename U>        int  ImportClsTmplMemTmpl<T>::StaticFieldDef; // expected-warning{{definition of dllimport static field}}
 template<typename T> template<typename U> const  int  ImportClsTmplMemTmpl<T>::StaticConstFieldDef = 1; // expected-warning{{definition of dllimport static field}}
-template<typename T> template<typename U> constexpr int ImportClsTmplMemTmpl<T>::ConstexprFieldDef; // expected-warning{{definition of dllimport static field}}
+#ifdef MS
+template<typename T> template<typename U> constexpr int ImportClsTmplMemTmpl<T>::ConstexprFieldDef;
+#endif
 #endif // __has_feature(cxx_variable_templates)
 
 
@@ -1353,7 +1391,9 @@ struct CTMTR /*ClassTmplMemberTmplRedecl*/ {
 #if __has_feature(cxx_variable_templates)
   template<typename U> static        int  StaticField;         // expected-note{{previous declaration is here}}
   template<typename U> static const  int  StaticConstField;    // expected-note{{previous declaration is here}}
-  template<typename U> constexpr static int ConstexprField = 1; // expected-note{{previous declaration is here}}
+#ifdef MS
+  template<typename U> constexpr static int ConstexprField = 1; // expected-note{{previous definition is here}}
+#endif
 #endif // __has_feature(cxx_variable_templates)
 };
 
@@ -1379,9 +1419,10 @@ template<typename T> template<typename U> __declspec(dllimport)        int  CTMT
 template<typename T> template<typename U> __declspec(dllimport) const  int  CTMTR<T>::StaticConstField = 1;  // expected-error{{redeclaration of 'CTMTR::StaticConstField' cannot add 'dllimport' attribute}}
                                                                                                              // expected-warning@-1{{definition of dllimport static field}}
                                                                                                              // expected-note@-2{{attribute is here}}
-template<typename T> template<typename U> __declspec(dllimport) constexpr int CTMTR<T>::ConstexprField;      // expected-error{{redeclaration of 'CTMTR::ConstexprField' cannot add 'dllimport' attribute}}
-                                                                                                             // expected-warning@-1{{definition of dllimport static field}}
-                                                                                                             // expected-note@-2{{attribute is here}}
+#ifdef MS
+// expected-warning@+1{{attribute declaration must precede definition}}
+template<typename T> template<typename U> __declspec(dllimport) constexpr int CTMTR<T>::ConstexprField;
+#endif
 #endif // __has_feature(cxx_variable_templates)