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

1 files changed, 10 insertions, 1 deletions

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);
   }