Fix our handling of visibility in explicit template instantiations.

* Don't copy the visibility attribute during instantiations. We have to be able
  to distinguish

 struct HIDDEN foo {};
 template<class T>
 DEFAULT void bar() {}
 template DEFAULT void bar<foo>();

from

 struct HIDDEN foo {};
 template<class T>
 DEFAULT void bar() {}
 template void bar<foo>();

* If an instantiation has an attribute, it takes precedence over an attribute
  in the template.

* With instantiation attributes handled with the above logic, we can now
  select the minimum visibility when looking at template arguments.

llvm-svn: 156821

1 files changed, 7 insertions, 9 deletions

diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index 15fa7902031..21405d223d1 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -158,14 +158,12 @@ getLVForTemplateArgumentList(const TemplateArgumentList &TArgs,
   return getLVForTemplateArgumentList(TArgs.data(), TArgs.size(), OnlyTemplate);
 }
 
-static bool shouldConsiderTemplateLV(const FunctionDecl *fn,
-                               const FunctionTemplateSpecializationInfo *spec) {
-  return !(spec->isExplicitSpecialization() &&
-           fn->hasAttr<VisibilityAttr>());
+static bool shouldConsiderTemplateLV(const FunctionDecl *fn) {
+  return !fn->hasAttr<VisibilityAttr>();
 }
 
 static bool shouldConsiderTemplateLV(const ClassTemplateSpecializationDecl *d) {
-  return !(d->isExplicitSpecialization() && d->hasAttr<VisibilityAttr>());
+  return !d->hasAttr<VisibilityAttr>();
 }
 
 static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D,
@@ -376,7 +374,7 @@ static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D,
     // this is an explicit specialization with a visibility attribute.
     if (FunctionTemplateSpecializationInfo *specInfo
                                = Function->getTemplateSpecializationInfo()) {
-      if (shouldConsiderTemplateLV(Function, specInfo)) {
+      if (shouldConsiderTemplateLV(Function)) {
         LV.merge(getLVForDecl(specInfo->getTemplate(),
                               true));
         const TemplateArgumentList &templateArgs = *specInfo->TemplateArguments;
@@ -407,8 +405,8 @@ static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D,
 
         // The arguments at which the template was instantiated.
         const TemplateArgumentList &TemplateArgs = spec->getTemplateArgs();
-        LV.merge(getLVForTemplateArgumentList(TemplateArgs,
-                                              OnlyTemplate));
+        LV.mergeWithMin(getLVForTemplateArgumentList(TemplateArgs,
+                                                     OnlyTemplate));
       }
     }
 
@@ -527,7 +525,7 @@ static LinkageInfo getLVForClassMember(const NamedDecl *D, bool OnlyTemplate) {
     // the template parameters and arguments.
     if (FunctionTemplateSpecializationInfo *spec
            = MD->getTemplateSpecializationInfo()) {
-      if (shouldConsiderTemplateLV(MD, spec)) {
+      if (shouldConsiderTemplateLV(MD)) {
         LV.mergeWithMin(getLVForTemplateArgumentList(*spec->TemplateArguments,
                                                      OnlyTemplate));
         if (!OnlyTemplate)