From: Dmitry Polukhin <dmitry.polukhin@gmail.com>
Date: Tue, 24 May 2016 06:37:14 +0000 (+0000)
Subject: [MSVC2015] dllexport for defaulted special class members
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=9251b827b680855c59255155745787ca32654d71;p=clang

[MSVC2015] dllexport for defaulted special class members

Clang doesn't dllexport defaulted special member function defaulted
inside class but does it if they defaulted outside class. MSVC doesn't
make any distinction where they were defaulted. Also MSVC 2013 and 2015
export different set of members. MSVC2015 doesn't emit trivial defaulted
x-tors but does emit copy assign operator.

Differential revision: http://reviews.llvm.org/D20422

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@270535 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index ca8ed71fce..38b4acfbdc 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -4811,11 +4811,17 @@ void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
         // MSVC versions before 2015 don't export the move assignment operators
         // and move constructor, so don't attempt to import/export them if
         // we have a definition.
-        auto *CXXC = dyn_cast<CXXConstructorDecl>(MD);
+        auto *Ctor = dyn_cast<CXXConstructorDecl>(MD);
         if ((MD->isMoveAssignmentOperator() ||
-             (CXXC && CXXC->isMoveConstructor())) &&
+             (Ctor && Ctor->isMoveConstructor())) &&
             !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015))
           continue;
+
+        // MSVC2015 doesn't export trivial defaulted x-tor but copy assign
+        // operator is exported anyway.
+        if (getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
+            (Ctor || isa<CXXDestructorDecl>(MD)) && MD->isTrivial())
+          continue;
       }
     }
 
@@ -4889,6 +4895,33 @@ void Sema::propagateDLLAttrToBaseClassTemplate(
   }
 }
 
+static void DefineImplicitSpecialMember(Sema &S, CXXMethodDecl *MD,
+                                        SourceLocation DefaultLoc) {
+  switch (S.getSpecialMember(MD)) {
+  case Sema::CXXDefaultConstructor:
+    S.DefineImplicitDefaultConstructor(DefaultLoc,
+                                       cast<CXXConstructorDecl>(MD));
+    break;
+  case Sema::CXXCopyConstructor:
+    S.DefineImplicitCopyConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
+    break;
+  case Sema::CXXCopyAssignment:
+    S.DefineImplicitCopyAssignment(DefaultLoc, MD);
+    break;
+  case Sema::CXXDestructor:
+    S.DefineImplicitDestructor(DefaultLoc, cast<CXXDestructorDecl>(MD));
+    break;
+  case Sema::CXXMoveConstructor:
+    S.DefineImplicitMoveConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
+    break;
+  case Sema::CXXMoveAssignment:
+    S.DefineImplicitMoveAssignment(DefaultLoc, MD);
+    break;
+  case Sema::CXXInvalid:
+    llvm_unreachable("Invalid special member.");
+  }
+}
+
 /// \brief Perform semantic checks on a class definition that has been
 /// completing, introducing implicitly-declared members, checking for
 /// abstract types, etc.
@@ -4984,8 +5017,8 @@ void Sema::CheckCompletedCXXClass(CXXRecordDecl *Record) {
 
       // For an explicitly defaulted or deleted special member, we defer
       // determining triviality until the class is complete. That time is now!
+      CXXSpecialMember CSM = getSpecialMember(M);
       if (!M->isImplicit() && !M->isUserProvided()) {
-        CXXSpecialMember CSM = getSpecialMember(M);
         if (CSM != CXXInvalid) {
           M->setTrivial(SpecialMemberIsTrivial(M, CSM));
 
@@ -4993,6 +5026,20 @@ void Sema::CheckCompletedCXXClass(CXXRecordDecl *Record) {
           Record->finishedDefaultedOrDeletedMember(M);
         }
       }
+
+      if (!M->isInvalidDecl() && M->isExplicitlyDefaulted() &&
+          M->hasAttr<DLLExportAttr>()) {
+        if (getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
+            M->isTrivial() &&
+            (CSM == CXXDefaultConstructor || CSM == CXXCopyConstructor ||
+             CSM == CXXDestructor))
+          M->dropAttr<DLLExportAttr>();
+
+        if (M->hasAttr<DLLExportAttr>()) {
+          DefineImplicitSpecialMember(*this, M, M->getLocation());
+          ActOnFinishInlineFunctionDef(M);
+        }
+      }
     }
   }
 
@@ -13063,32 +13110,8 @@ void Sema::SetDeclDefaulted(Decl *Dcl, SourceLocation DefaultLoc) {
 
     CheckExplicitlyDefaultedSpecialMember(MD);
 
-    if (MD->isInvalidDecl())
-      return;
-
-    switch (Member) {
-    case CXXDefaultConstructor:
-      DefineImplicitDefaultConstructor(DefaultLoc,
-                                       cast<CXXConstructorDecl>(MD));
-      break;
-    case CXXCopyConstructor:
-      DefineImplicitCopyConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
-      break;
-    case CXXCopyAssignment:
-      DefineImplicitCopyAssignment(DefaultLoc, MD);
-      break;
-    case CXXDestructor:
-      DefineImplicitDestructor(DefaultLoc, cast<CXXDestructorDecl>(MD));
-      break;
-    case CXXMoveConstructor:
-      DefineImplicitMoveConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
-      break;
-    case CXXMoveAssignment:
-      DefineImplicitMoveAssignment(DefaultLoc, MD);
-      break;
-    case CXXInvalid:
-      llvm_unreachable("Invalid special member.");
-    }
+    if (!MD->isInvalidDecl())
+      DefineImplicitSpecialMember(*this, MD, DefaultLoc);
   } else {
     Diag(DefaultLoc, diag::err_default_special_members);
   }
diff --git a/test/CodeGenCXX/dllexport-members.cpp b/test/CodeGenCXX/dllexport-members.cpp
index 76f692dbd3..1c56251328 100644
--- a/test/CodeGenCXX/dllexport-members.cpp
+++ b/test/CodeGenCXX/dllexport-members.cpp
@@ -1,5 +1,7 @@
-// RUN: %clang_cc1 -triple i686-windows-msvc -fms-compatibility   -emit-llvm -std=c++1y -O0 -o - %s | FileCheck --check-prefix=MSC --check-prefix=M32 %s
-// RUN: %clang_cc1 -triple x86_64-windows-msvc -fms-compatibility -emit-llvm -std=c++1y -O0 -o - %s | FileCheck --check-prefix=MSC --check-prefix=M64 %s
+// RUN: %clang_cc1 -triple i686-windows-msvc   -fms-compatibility -fms-compatibility-version=18 -emit-llvm -std=c++1y -O0 -o - %s | FileCheck --check-prefix=MSC --check-prefix=M32 %s
+// RUN: %clang_cc1 -triple x86_64-windows-msvc -fms-compatibility -fms-compatibility-version=18 -emit-llvm -std=c++1y -O0 -o - %s | FileCheck --check-prefix=MSC --check-prefix=M64 %s
+// RUN: %clang_cc1 -triple i686-windows-msvc   -fms-compatibility -fms-compatibility-version=19 -emit-llvm -std=c++1y -O0 -o - %s | FileCheck --check-prefix=M32VS2015 %s
+// RUN: %clang_cc1 -triple x86_64-windows-msvc -fms-compatibility -fms-compatibility-version=19 -emit-llvm -std=c++1y -O0 -o - %s | FileCheck --check-prefix=M64VS2015 %s
 // RUN: %clang_cc1 -triple i686-windows-gnu                       -emit-llvm -std=c++1y -O0 -o - %s | FileCheck --check-prefix=GNU --check-prefix=G32 %s
 // RUN: %clang_cc1 -triple x86_64-windows-gnu                     -emit-llvm -std=c++1y -O0 -o - %s | FileCheck --check-prefix=GNU --check-prefix=G64 %s
 
@@ -427,6 +429,32 @@ __declspec(dllexport) ExportDefaultedDefs::ExportDefaultedDefs(ExportDefaultedDe
 ExportDefaultedDefs& ExportDefaultedDefs::operator=(ExportDefaultedDefs&&) = default;
 
 
+// Export defaulted member function definitions declared inside class.
+struct ExportDefaultedInclassDefs {
+  __declspec(dllexport) ExportDefaultedInclassDefs() = default;
+  // M32VS2013-DAG: define weak_odr dllexport x86_thiscallcc %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QAE@XZ"(%struct.ExportDefaultedInclassDefs* returned %this)
+  // M64VS2013-DAG: define weak_odr dllexport                %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QEAA@XZ"(%struct.ExportDefaultedInclassDefs* returned %this)
+  // M32VS2015-NOT: define weak_odr dllexport x86_thiscallcc %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QAE@XZ"(%struct.ExportDefaultedInclassDefs* returned %this)
+  // M64VS2015-NOT: define weak_odr dllexport                %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QEAA@XZ"(%struct.ExportDefaultedInclassDefs* returned %this)
+
+  __declspec(dllexport) ~ExportDefaultedInclassDefs() = default;
+  // M32VS2013-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??1ExportDefaultedInclassDefs@@QAE@XZ"(%struct.ExportDefaultedInclassDefs* %this)
+  // M64VS2013-DAG: define weak_odr dllexport                void @"\01??1ExportDefaultedInclassDefs@@QEAA@XZ"(%struct.ExportDefaultedInclassDefs* %this)
+  // M32VS2015-NOT: define weak_odr dllexport x86_thiscallcc void @"\01??1ExportDefaultedInclassDefs@@QAE@XZ"(%struct.ExportDefaultedInclassDefs* %this)
+  // M64VS2015-NOT: define weak_odr dllexport                void @"\01??1ExportDefaultedInclassDefs@@QEAA@XZ"(%struct.ExportDefaultedInclassDefs* %this)
+
+  __declspec(dllexport) ExportDefaultedInclassDefs(const ExportDefaultedInclassDefs&) = default;
+  // M32VS2013-DAG: define weak_odr dllexport x86_thiscallcc %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QAE@ABU0@@Z"(%struct.ExportDefaultedInclassDefs* returned %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+  // M64VS2013-DAG: define weak_odr dllexport                %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QEAA@AEBU0@@Z"(%struct.ExportDefaultedInclassDefs* returned %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+  // M32VS2015-NOT: define weak_odr dllexport x86_thiscallcc %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QAE@ABU0@@Z"(%struct.ExportDefaultedInclassDefs* returned %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+  // M64VS2015-NOT: define weak_odr dllexport                %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QEAA@AEBU0@@Z"(%struct.ExportDefaultedInclassDefs* returned %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+
+  __declspec(dllexport) ExportDefaultedInclassDefs& operator=(const ExportDefaultedInclassDefs&) = default;
+  // M32-DAG: define weak_odr dllexport x86_thiscallcc dereferenceable({{[0-9]+}}) %struct.ExportDefaultedInclassDefs* @"\01??4ExportDefaultedInclassDefs@@QAEAAU0@ABU0@@Z"(%struct.ExportDefaultedInclassDefs* %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+  // M64-DAG: define weak_odr dllexport                dereferenceable({{[0-9]+}}) %struct.ExportDefaultedInclassDefs* @"\01??4ExportDefaultedInclassDefs@@QEAAAEAU0@AEBU0@@Z"(%struct.ExportDefaultedInclassDefs* %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+};
+
+
 // Export allocation functions.
 struct ExportAlloc {
   __declspec(dllexport) void* operator new(__SIZE_TYPE__);
diff --git a/test/CodeGenCXX/dllexport.cpp b/test/CodeGenCXX/dllexport.cpp
index a975924456..6232f2c747 100644
--- a/test/CodeGenCXX/dllexport.cpp
+++ b/test/CodeGenCXX/dllexport.cpp
@@ -1,8 +1,8 @@
-// RUN: %clang_cc1 -triple i686-windows-msvc   -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O1 -mconstructor-aliases -disable-llvm-optzns -o - %s -w -fms-compatibility-version=19.00 | FileCheck --check-prefix=MSC --check-prefix=M32 -check-prefix=MSVC2015 %s
-// RUN: %clang_cc1 -triple i686-windows-msvc   -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O1 -mconstructor-aliases -disable-llvm-optzns -o - %s -w -fms-compatibility-version=18.00 | FileCheck --check-prefix=MSC --check-prefix=M32 -check-prefix=MSVC2013 %s
+// RUN: %clang_cc1 -triple i686-windows-msvc   -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O1 -mconstructor-aliases -disable-llvm-optzns -o - %s -w -fms-compatibility-version=19.00 | FileCheck --check-prefix=MSC --check-prefix=M32 -check-prefix=MSVC2015 -check-prefix=M32MSVC2015 %s
+// RUN: %clang_cc1 -triple i686-windows-msvc   -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O1 -mconstructor-aliases -disable-llvm-optzns -o - %s -w -fms-compatibility-version=18.00 | FileCheck --check-prefix=MSC --check-prefix=M32 -check-prefix=MSVC2013 -check-prefix=M32MSVC2013 %s
 
-// RUN: %clang_cc1 -triple x86_64-windows-msvc -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O0 -o - %s -w -fms-compatibility-version=19.00 | FileCheck --check-prefix=MSC --check-prefix=M64 -check-prefix=MSVC2015 %s
-// RUN: %clang_cc1 -triple x86_64-windows-msvc -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O0 -o - %s -w -fms-compatibility-version=18.00 | FileCheck --check-prefix=MSC --check-prefix=M64 -check-prefix=MSVC2013 %s
+// RUN: %clang_cc1 -triple x86_64-windows-msvc -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O0 -o - %s -w -fms-compatibility-version=19.00 | FileCheck --check-prefix=MSC --check-prefix=M64 -check-prefix=MSVC2015 -check-prefix=M64MSVC2015 %s
+// RUN: %clang_cc1 -triple x86_64-windows-msvc -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O0 -o - %s -w -fms-compatibility-version=18.00 | FileCheck --check-prefix=MSC --check-prefix=M64 -check-prefix=MSVC2013 -check-prefix=M64MSVC2013 %s
 
 // RUN: %clang_cc1 -triple i686-windows-gnu    -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O0 -o - %s -w | FileCheck --check-prefix=GNU --check-prefix=G32 %s
 // RUN: %clang_cc1 -triple x86_64-windows-gnu  -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O0 -o - %s -w | FileCheck --check-prefix=GNU --check-prefix=G64 %s
@@ -561,7 +561,7 @@ struct __declspec(dllexport) T {
 
   // Explicitly defaulted copy constructur:
   T(const T&) = default;
-  // M32-DAG: define weak_odr dllexport x86_thiscallcc %struct.T* @"\01??0T@@QAE@ABU0@@Z"
+  // M32MSVC2013-DAG: define weak_odr dllexport x86_thiscallcc %struct.T* @"\01??0T@@QAE@ABU0@@Z"
 
   void a() {}
   // M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01?a@T@@QAEXXZ"
@@ -647,9 +647,34 @@ namespace UseDtorAlias {
 
 struct __declspec(dllexport) DefaultedCtorsDtors {
   DefaultedCtorsDtors() = default;
-  // M32-DAG: define weak_odr dllexport x86_thiscallcc %struct.DefaultedCtorsDtors* @"\01??0DefaultedCtorsDtors@@QAE@XZ"
+  // M32MSVC2013-DAG: define weak_odr dllexport x86_thiscallcc %struct.DefaultedCtorsDtors* @"\01??0DefaultedCtorsDtors@@QAE@XZ"
   ~DefaultedCtorsDtors() = default;
-  // M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??1DefaultedCtorsDtors@@QAE@XZ"
+  // M32MSVC2013-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??1DefaultedCtorsDtors@@QAE@XZ"
+};
+
+// Export defaulted member function definitions declared inside class.
+struct __declspec(dllexport) ExportDefaultedInclassDefs {
+  ExportDefaultedInclassDefs() = default;
+  // M32VS2013-DAG: define weak_odr dllexport x86_thiscallcc %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QAE@XZ"(%struct.ExportDefaultedInclassDefs* returned %this)
+  // M64VS2013-DAG: define weak_odr dllexport                %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QEAA@XZ"(%struct.ExportDefaultedInclassDefs* returned %this)
+  // M32VS2015-NOT: define weak_odr dllexport x86_thiscallcc %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QAE@XZ"(%struct.ExportDefaultedInclassDefs* returned %this)
+  // M64VS2015-NOT: define weak_odr dllexport                %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QEAA@XZ"(%struct.ExportDefaultedInclassDefs* returned %this)
+
+  ~ExportDefaultedInclassDefs() = default;
+  // M32VS2013-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??1ExportDefaultedInclassDefs@@QAE@XZ"(%struct.ExportDefaultedInclassDefs* %this)
+  // M64VS2013-DAG: define weak_odr dllexport                void @"\01??1ExportDefaultedInclassDefs@@QEAA@XZ"(%struct.ExportDefaultedInclassDefs* %this)
+  // M32VS2015-NOT: define weak_odr dllexport x86_thiscallcc void @"\01??1ExportDefaultedInclassDefs@@QAE@XZ"(%struct.ExportDefaultedInclassDefs* %this)
+  // M64VS2015-NOT: define weak_odr dllexport                void @"\01??1ExportDefaultedInclassDefs@@QEAA@XZ"(%struct.ExportDefaultedInclassDefs* %this)
+
+  ExportDefaultedInclassDefs(const ExportDefaultedInclassDefs&) = default;
+  // M32VS2013-DAG: define weak_odr dllexport x86_thiscallcc %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QAE@ABU0@@Z"(%struct.ExportDefaultedInclassDefs* returned %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+  // M64VS2013-DAG: define weak_odr dllexport                %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QEAA@AEBU0@@Z"(%struct.ExportDefaultedInclassDefs* returned %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+  // M32VS2015-NOT: define weak_odr dllexport x86_thiscallcc %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QAE@ABU0@@Z"(%struct.ExportDefaultedInclassDefs* returned %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+  // M64VS2015-NOT: define weak_odr dllexport                %struct.ExportDefaultedInclassDefs* @"\01??0ExportDefaultedInclassDefs@@QEAA@AEBU0@@Z"(%struct.ExportDefaultedInclassDefs* returned %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+
+  ExportDefaultedInclassDefs& operator=(const ExportDefaultedInclassDefs&) = default;
+  // M32-DAG: define weak_odr dllexport x86_thiscallcc dereferenceable({{[0-9]+}}) %struct.ExportDefaultedInclassDefs* @"\01??4ExportDefaultedInclassDefs@@QAEAAU0@ABU0@@Z"(%struct.ExportDefaultedInclassDefs* %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
+  // M64-DAG: define weak_odr dllexport                dereferenceable({{[0-9]+}}) %struct.ExportDefaultedInclassDefs* @"\01??4ExportDefaultedInclassDefs@@QEAAAEAU0@AEBU0@@Z"(%struct.ExportDefaultedInclassDefs* %this, %struct.ExportDefaultedInclassDefs* dereferenceable({{[0-9]+}}))
 };
 
 namespace ReferencedInlineMethodInNestedClass {
@@ -721,7 +746,7 @@ template <typename T> struct ExplicitInstConstexprMembers {
   // M32-DAG: define weak_odr dllexport x86_thiscallcc %struct.ExplicitInstConstexprMembers* @"\01??0?$ExplicitInstConstexprMembers@X@@QAE@XZ"
 
   ExplicitInstConstexprMembers(const ExplicitInstConstexprMembers&) = default;
-  // M32-DAG: define weak_odr dllexport x86_thiscallcc %struct.ExplicitInstConstexprMembers* @"\01??0?$ExplicitInstConstexprMembers@X@@QAE@ABU0@@Z"
+  // M32MSVC2013-DAG: define weak_odr dllexport x86_thiscallcc %struct.ExplicitInstConstexprMembers* @"\01??0?$ExplicitInstConstexprMembers@X@@QAE@ABU0@@Z"
 
   constexpr int f() const { return 42; }
   // M32-DAG: define weak_odr dllexport x86_thiscallcc i32 @"\01?f@?$ExplicitInstConstexprMembers@X@@QBEHXZ"