[ms][dll] #27212: Generating of implicit special members should take into account MSVC compatibility version

Clang creates implicit move constructor/assign operator in all cases if
there is std=c++11. But MSVC supports such generation starting from
version 1900 only. As result we have some binary incompatibility.

Differential Revision: http://reviews.llvm.org/D19156

Patch by Andrew V. Tischenko

llvm-svn: 269400

2 files changed, 26 insertions, 7 deletions

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index e3cca7f8105..96c47e29ef3 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -4774,7 +4774,6 @@ void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
 
   // The class is either imported or exported.
   const bool ClassExported = ClassAttr->getKind() == attr::DLLExport;
-  const bool ClassImported = !ClassExported;
 
   TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
 
@@ -4809,9 +4808,12 @@ void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
         if (!Context.getTargetInfo().getCXXABI().isMicrosoft())
           continue;
 
-        // MSVC versions before 2015 don't export the move assignment operators,
-        // so don't attempt to import them if we have a definition.
-        if (ClassImported && MD->isMoveAssignmentOperator() &&
+        // 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);
+        if ((MD->isMoveAssignmentOperator() ||
+             (CXXC && CXXC->isMoveConstructor())) &&
             !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015))
           continue;
       }
diff --git a/clang/test/CodeGenCXX/dllexport.cpp b/clang/test/CodeGenCXX/dllexport.cpp
index c839242e43f..a9759244564 100644
--- a/clang/test/CodeGenCXX/dllexport.cpp
+++ b/clang/test/CodeGenCXX/dllexport.cpp
@@ -1,5 +1,9 @@
-// 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 | FileCheck --check-prefix=MSC --check-prefix=M32 %s
-// RUN: %clang_cc1 -triple x86_64-windows-msvc -emit-llvm -std=c++1y -fno-threadsafe-statics -fms-extensions -O0 -o - %s -w | FileCheck --check-prefix=MSC --check-prefix=M64 %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 %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 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 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
 
@@ -528,6 +532,8 @@ struct SomeTemplate {
   SomeTemplate(T o = T()) : o(o) {}
   T o;
 };
+// MSVC2015-DAG: define weak_odr dllexport {{.+}} @"\01??4?$SomeTemplate@H@@Q{{.+}}@$$Q{{.+}}@@Z"
+// MSVC2013-DAG: define weak_odr dllexport {{.+}} @"\01??4?$SomeTemplate@H@@Q{{.+}}0@A{{.+}}0@@Z"
 struct __declspec(dllexport) InheritFromTemplate : SomeTemplate<int> {};
 
 // M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01??_F?$SomeTemplate@H@@QAEXXZ"({{.*}}) {{#[0-9]+}} comdat
@@ -616,7 +622,8 @@ struct __declspec(dllexport) X : public virtual W {};
 
 struct __declspec(dllexport) Y {
   // Move assignment operator:
-  // M32-DAG: define weak_odr dllexport x86_thiscallcc dereferenceable({{[0-9]+}}) %struct.Y* @"\01??4Y@@QAEAAU0@$$QAU0@@Z"
+  // MSVC2015-DAG: define weak_odr dllexport {{.+}} @"\01??4Y@@Q{{.+}}@$$Q{{.+}}@@Z"
+  // MSVC2013-DAG: define weak_odr dllexport {{.+}} @"\01??4Y@@Q{{.+}}0@A{{.+}}0@@Z"
 
   int x;
 };
@@ -947,3 +954,13 @@ struct __declspec(dllexport) LayerTreeImpl {
 };
 // M32-DAG: define weak_odr dllexport x86_thiscallcc %"struct.LayerTreeImpl::ElementLayers"* @"\01??0ElementLayers@LayerTreeImpl@@QAE@XZ"
 // M64-DAG: define weak_odr dllexport %"struct.LayerTreeImpl::ElementLayers"* @"\01??0ElementLayers@LayerTreeImpl@@QEAA@XZ"
+
+class __declspec(dllexport) ACE_Shared_Object {
+public:
+  virtual ~ACE_Shared_Object();
+};
+class __declspec(dllexport) ACE_Service_Object : public ACE_Shared_Object {};
+// Implicit move constructor declaration.
+// MSVC2015-DAG: define weak_odr dllexport {{.+}}ACE_Service_Object@@Q{{.+}}@$$Q
+// The declarations should not be exported.
+// MSVC2013-NOT: define weak_odr dllexport {{.+}}ACE_Service_Object@@Q{{.+}}@$$Q