clang-cl: Handle dll attributes in explicit class template specialization definitions (PR23667)

Previously, we wouldn't call checkDLLAttribute() after the class template
specialization definition if the class template was already instantiated
by an explicit class template specialization declaration.

llvm-svn: 238266

5 files changed, 46 insertions, 19 deletions

diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index a7020589e85..39ea3c62a87 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -5109,6 +5109,7 @@ public:
                             ArrayRef<CXXCtorInitializer*> MemInits,
                             bool AnyErrors);
 
+  void checkClassLevelDLLAttribute(CXXRecordDecl *Class);
   void CheckCompletedCXXClass(CXXRecordDecl *Record);
   void ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc,
                                          Decl *TagDecl,
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index e52d29e45c5..b1dfe0e95e2 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -4739,15 +4739,15 @@ static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
 }
 
 /// \brief Check class-level dllimport/dllexport attribute.
-static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
+void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
   Attr *ClassAttr = getDLLAttr(Class);
 
   // MSVC inherits DLL attributes to partial class template specializations.
-  if (S.Context.getTargetInfo().getCXXABI().isMicrosoft() && !ClassAttr) {
+  if (Context.getTargetInfo().getCXXABI().isMicrosoft() && !ClassAttr) {
     if (auto *Spec = dyn_cast<ClassTemplatePartialSpecializationDecl>(Class)) {
       if (Attr *TemplateAttr =
               getDLLAttr(Spec->getSpecializedTemplate()->getTemplatedDecl())) {
-        auto *A = cast<InheritableAttr>(TemplateAttr->clone(S.getASTContext()));
+        auto *A = cast<InheritableAttr>(TemplateAttr->clone(getASTContext()));
         A->setInherited(true);
         ClassAttr = A;
       }
@@ -4758,12 +4758,12 @@ static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
     return;
 
   if (!Class->isExternallyVisible()) {
-    S.Diag(Class->getLocation(), diag::err_attribute_dll_not_extern)
+    Diag(Class->getLocation(), diag::err_attribute_dll_not_extern)
         << Class << ClassAttr;
     return;
   }
 
-  if (S.Context.getTargetInfo().getCXXABI().isMicrosoft() &&
+  if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
       !ClassAttr->isInherited()) {
     // Diagnose dll attributes on members of class with dll attribute.
     for (Decl *Member : Class->decls()) {
@@ -4773,10 +4773,10 @@ static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
       if (!MemberAttr || MemberAttr->isInherited() || Member->isInvalidDecl())
         continue;
 
-      S.Diag(MemberAttr->getLocation(),
+      Diag(MemberAttr->getLocation(),
              diag::err_attribute_dll_member_of_dll_class)
           << MemberAttr << ClassAttr;
-      S.Diag(ClassAttr->getLocation(), diag::note_previous_attribute);
+      Diag(ClassAttr->getLocation(), diag::note_previous_attribute);
       Member->setInvalidDecl();
     }
   }
@@ -4798,7 +4798,7 @@ static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
   }
 
   // Force declaration of implicit members so they can inherit the attribute.
-  S.ForceDeclarationOfImplicitMembers(Class);
+  ForceDeclarationOfImplicitMembers(Class);
 
   // FIXME: MSVC's docs say all bases must be exportable, but this doesn't
   // seem to be true in practice?
@@ -4818,13 +4818,13 @@ static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
 
       if (MD->isInlined()) {
         // MinGW does not import or export inline methods.
-        if (!S.Context.getTargetInfo().getCXXABI().isMicrosoft())
+        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() &&
-            !S.getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015))
+            !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015))
           continue;
       }
     }
@@ -4834,7 +4834,7 @@ static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
 
     if (!getDLLAttr(Member)) {
       auto *NewAttr =
-          cast<InheritableAttr>(ClassAttr->clone(S.getASTContext()));
+          cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
       NewAttr->setInherited(true);
       Member->addAttr(NewAttr);
     }
@@ -4849,7 +4849,7 @@ static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
         if (TSK == TSK_ImplicitInstantiation && !ClassAttr->isInherited())
           continue;
 
-        S.MarkFunctionReferenced(Class->getLocation(), MD);
+        MarkFunctionReferenced(Class->getLocation(), MD);
 
         // The function will be passed to the consumer when its definition is
         // encountered.
@@ -4860,17 +4860,17 @@ static void checkDLLAttribute(Sema &S, CXXRecordDecl *Class) {
         // defaulted methods, and the copy and move assignment operators. The
         // latter are exported even if they are trivial, because the address of
         // an operator can be taken and should compare equal accross libraries.
-        DiagnosticErrorTrap Trap(S.Diags);
-        S.MarkFunctionReferenced(Class->getLocation(), MD);
+        DiagnosticErrorTrap Trap(Diags);
+        MarkFunctionReferenced(Class->getLocation(), MD);
         if (Trap.hasErrorOccurred()) {
-          S.Diag(ClassAttr->getLocation(), diag::note_due_to_dllexported_class)
-              << Class->getName() << !S.getLangOpts().CPlusPlus11;
+          Diag(ClassAttr->getLocation(), diag::note_due_to_dllexported_class)
+              << Class->getName() << !getLangOpts().CPlusPlus11;
           break;
         }
 
         // There is no later point when we will see the definition of this
         // function, so pass it to the consumer now.
-        S.Consumer.HandleTopLevelDecl(DeclGroupRef(MD));
+        Consumer.HandleTopLevelDecl(DeclGroupRef(MD));
       }
     }
   }
@@ -5014,7 +5014,7 @@ void Sema::CheckCompletedCXXClass(CXXRecordDecl *Record) {
   //   have inheriting constructors.
   DeclareInheritingConstructors(Record);
 
-  checkDLLAttribute(*this, Record);
+  checkClassLevelDLLAttribute(Record);
 }
 
 /// Look up the special member function that would be called by a special
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index b5d04cf1a12..37eeee2f886 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -7365,10 +7365,19 @@ Sema::ActOnExplicitInstantiation(Scope *S,
     // Fix a TSK_ExplicitInstantiationDeclaration followed by a
     // TSK_ExplicitInstantiationDefinition
     if (Old_TSK == TSK_ExplicitInstantiationDeclaration &&
-        TSK == TSK_ExplicitInstantiationDefinition)
+        TSK == TSK_ExplicitInstantiationDefinition) {
       // FIXME: Need to notify the ASTMutationListener that we did this.
       Def->setTemplateSpecializationKind(TSK);
 
+      if (!getDLLAttr(Def) && getDLLAttr(Specialization)) {
+        auto *A = cast<InheritableAttr>(
+            getDLLAttr(Specialization)->clone(getASTContext()));
+        A->setInherited(true);
+        Def->addAttr(A);
+        checkClassLevelDLLAttribute(Def);
+      }
+    }
+
     InstantiateClassTemplateSpecializationMembers(TemplateNameLoc, Def, TSK);
   }
 
diff --git a/clang/test/CodeGenCXX/dllexport.cpp b/clang/test/CodeGenCXX/dllexport.cpp
index bc1486f0d7d..3a1a3ffd871 100644
--- a/clang/test/CodeGenCXX/dllexport.cpp
+++ b/clang/test/CodeGenCXX/dllexport.cpp
@@ -691,6 +691,11 @@ extern template struct ExplicitInstantiationDeclExportedTemplate<int>;
 USEMEMFUNC(ExplicitInstantiationDeclExportedTemplate<int>, f);
 // M32-DAG: {{declare|define available_externally}} x86_thiscallcc void @"\01?f@?$ExplicitInstantiationDeclExportedTemplate@H@@QAEXXZ"
 
+template <typename T> struct ExplicitInstantiationDeclExportedDefTemplate { void f() {} };
+extern template struct ExplicitInstantiationDeclExportedDefTemplate<int>;
+template struct __declspec(dllexport) ExplicitInstantiationDeclExportedDefTemplate<int>;
+// M32-DAG: define weak_odr dllexport x86_thiscallcc void @"\01?f@?$ExplicitInstantiationDeclExportedDefTemplate@H@@QAEXXZ"
+
 namespace { struct InternalLinkageType {}; }
 struct __declspec(dllexport) PR23308 {
   void f(InternalLinkageType*);
diff --git a/clang/test/CodeGenCXX/dllimport.cpp b/clang/test/CodeGenCXX/dllimport.cpp
index 639baea5a3d..6de856017b5 100644
--- a/clang/test/CodeGenCXX/dllimport.cpp
+++ b/clang/test/CodeGenCXX/dllimport.cpp
@@ -724,6 +724,18 @@ template struct __declspec(dllimport) ExplicitlyInstantiatedWithDifferentAttr<in
 USEMEMFUNC(ExplicitlyInstantiatedWithDifferentAttr<int>, f);
 // M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc void @"\01?f@?$ExplicitlyInstantiatedWithDifferentAttr@H@@QAEXXZ"
 
+template <typename T> struct ExplicitInstantiationDeclImportedDefTemplate { void f() {} };
+extern template struct ExplicitInstantiationDeclImportedDefTemplate<int>;
+template struct __declspec(dllimport) ExplicitInstantiationDeclImportedDefTemplate<int>;
+USEMEMFUNC(ExplicitInstantiationDeclImportedDefTemplate<int>, f);
+// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc void @"\01?f@?$ExplicitInstantiationDeclImportedDefTemplate@H@@QAEXXZ"
+
+template <typename T> struct __declspec(dllimport) ExplicitInstantiationDeclExportedDefImportedTemplate { void f() {} };
+extern template struct __declspec(dllimport) ExplicitInstantiationDeclExportedDefImportedTemplate <int>;
+template struct __declspec(dllexport) ExplicitInstantiationDeclExportedDefImportedTemplate<int>;
+USEMEMFUNC(ExplicitInstantiationDeclExportedDefImportedTemplate<int>, f);
+// M32-DAG: {{declare|define available_externally}} dllimport x86_thiscallcc void @"\01?f@?$ExplicitInstantiationDeclExportedDefImportedTemplate@H@@QAEXXZ"
+
 
 //===----------------------------------------------------------------------===//
 // Classes with template base classes