Don't warn about not being able to propagate dll attribute to a base class template
when that base already has a different attribute.
MSVC doesn't actually try to do this; the first attribute that was propagated
takes precedence, so Clang is already doing the right thing and there's no
need to warn.
(This is a step towards fixing PR21718.)
llvm-svn: 239372
"attribute %q0 cannot be applied to member of %q1 class">;
def warn_attribute_dll_instantiated_base_class : Warning<
"propagating dll attribute to %select{already instantiated|explicitly specialized}0 "
- "base class template "
- "%select{without dll attribute|with different dll attribute}1 is not supported">,
+ "base class template without dll attribute is not supported">,
InGroup<DiagGroup<"unsupported-dll-base-class-template">>, DefaultIgnore;
def err_attribute_weakref_not_static : Error<
"weakref declaration must have internal linkage">;
return;
}
- bool DifferentAttribute = false;
- if (Attr *SpecializationAttr = getDLLAttr(BaseTemplateSpec)) {
- if (!SpecializationAttr->isInherited()) {
- // The template has previously been specialized or instantiated with an
- // explicit attribute. We should not try to change it.
- return;
- }
- if (SpecializationAttr->getKind() == ClassAttr->getKind()) {
- // The specialization already has the right attribute.
- return;
- }
- DifferentAttribute = true;
+ if (getDLLAttr(BaseTemplateSpec)) {
+ // The template has already been specialized or instantiated with an
+ // attribute, explicitly or through propagation. We should not try to change
+ // it.
+ return;
}
// The template was previously instantiated or explicitly specialized without
- // a dll attribute, or the template was previously instantiated with a
- // different inherited attribute. It's too late for us to change the
- // attribute, so warn that this is unsupported.
+ // a dll attribute, It's too late for us to add an attribute, so warn that
+ // this is unsupported.
S.Diag(BaseLoc, diag::warn_attribute_dll_instantiated_base_class)
- << BaseTemplateSpec->isExplicitSpecialization() << DifferentAttribute;
+ << BaseTemplateSpec->isExplicitSpecialization();
S.Diag(ClassAttr->getLocation(), diag::note_attribute);
if (BaseTemplateSpec->isExplicitSpecialization()) {
S.Diag(BaseTemplateSpec->getLocation(),
class DerivedFromTemplateD : public ClassTemplate<double> {};
class __declspec(dllexport) DerivedFromTemplateD2 : public ClassTemplate<double> {};
-#ifdef MS
-// expected-note@+4{{class template 'ClassTemplate<bool>' was instantiated here}}
-// expected-warning@+4{{propagating dll attribute to already instantiated base class template with different dll attribute is not supported}}
-// expected-note@+3{{attribute is here}}
-#endif
-class __declspec(dllimport) DerivedFromTemplateB : public ClassTemplate<bool> {};
-class __declspec(dllexport) DerivedFromTemplateB2 : public ClassTemplate<bool> {};
+class __declspec(dllexport) DerivedFromTemplateB : public ClassTemplate<bool> {};
+// The second derived class doesn't change anything, the attribute that was propagated first wins.
+class __declspec(dllimport) DerivedFromTemplateB2 : public ClassTemplate<bool> {};
#ifdef MS
// expected-warning@+3{{propagating dll attribute to explicitly specialized base class template without dll attribute is not supported}}
class DerivedFromTemplateD : public ClassTemplate<double> {};
class __declspec(dllimport) DerivedFromTemplateD2 : public ClassTemplate<double> {};
-#ifdef MS
-// expected-note@+4{{class template 'ClassTemplate<bool>' was instantiated here}}
-// expected-warning@+4{{propagating dll attribute to already instantiated base class template with different dll attribute is not supported}}
-// expected-note@+3{{attribute is here}}
-#endif
-class __declspec(dllexport) DerivedFromTemplateB : public ClassTemplate<bool> {};
-class __declspec(dllimport) DerivedFromTemplateB2 : public ClassTemplate<bool> {};
+class __declspec(dllimport) DerivedFromTemplateB : public ClassTemplate<bool> {};
+// The second derived class doesn't change anything, the attribute that was propagated first wins.
+class __declspec(dllexport) DerivedFromTemplateB2 : public ClassTemplate<bool> {};
template <typename T> struct ExplicitlySpecializedTemplate { void func() {} };
#ifdef MS