Implement a specific diagnostic when a class template partial
specialization does not use any of its template parameters, then
recover far more gracefully. Fixes PR6181.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@95629 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 5849d9b..05dca15 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1271,6 +1271,8 @@
"class template partial specialization %0 cannot be redeclared">;
def note_prev_partial_spec_here : Note<
"previous declaration of class template partial specialization %0 is here">;
+def err_partial_spec_fully_specialized : Error<
+ "partial specialization of %0 does not use any of its template parameters">;
// C++ Function template specializations
def err_function_template_spec_no_match : Error<
diff --git a/lib/Sema/SemaTemplate.cpp b/lib/Sema/SemaTemplate.cpp
index b77702b..1779bde 100644
--- a/lib/Sema/SemaTemplate.cpp
+++ b/lib/Sema/SemaTemplate.cpp
@@ -3400,12 +3400,23 @@
// FIXME: Diagnose friend partial specializations
- // FIXME: Template parameter list matters, too
- ClassTemplatePartialSpecializationDecl::Profile(ID,
- Converted.getFlatArguments(),
- Converted.flatSize(),
- Context);
- } else
+ if (!Name.isDependent() &&
+ !TemplateSpecializationType::anyDependentTemplateArguments(
+ TemplateArgs.getArgumentArray(),
+ TemplateArgs.size())) {
+ Diag(TemplateNameLoc, diag::err_partial_spec_fully_specialized)
+ << ClassTemplate->getDeclName();
+ isPartialSpecialization = false;
+ } else {
+ // FIXME: Template parameter list matters, too
+ ClassTemplatePartialSpecializationDecl::Profile(ID,
+ Converted.getFlatArguments(),
+ Converted.flatSize(),
+ Context);
+ }
+ }
+
+ if (!isPartialSpecialization)
ClassTemplateSpecializationDecl::Profile(ID,
Converted.getFlatArguments(),
Converted.flatSize(),
@@ -3435,7 +3446,7 @@
QualType CanonType;
if (PrevDecl &&
(PrevDecl->getSpecializationKind() == TSK_Undeclared ||
- TUK == TUK_Friend)) {
+ TUK == TUK_Friend)) {
// Since the only prior class template specialization with these
// arguments was referenced but not declared, or we're only
// referencing this specialization as a friend, reuse that
@@ -3448,8 +3459,8 @@
} else if (isPartialSpecialization) {
// Build the canonical type that describes the converted template
// arguments of the class template partial specialization.
- CanonType = Context.getTemplateSpecializationType(
- TemplateName(ClassTemplate),
+ TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name);
+ CanonType = Context.getTemplateSpecializationType(CanonTemplate,
Converted.getFlatArguments(),
Converted.flatSize());
diff --git a/test/SemaTemplate/temp_class_spec.cpp b/test/SemaTemplate/temp_class_spec.cpp
index e86f07a..8a07fd7 100644
--- a/test/SemaTemplate/temp_class_spec.cpp
+++ b/test/SemaTemplate/temp_class_spec.cpp
@@ -348,3 +348,16 @@
{
};
}
+
+namespace PR6181 {
+ template <class T>
+ class a;
+
+ class s;
+
+ template <class U>
+ class a<s> // expected-error{{partial specialization of 'a' does not use any of its template parameters}}
+ {
+ };
+
+}