PR32185: Revert r291512 and add a testcase for PR32185.
This reverts an attempt to check that types match when matching a
dependently-typed non-type template parameter. (This comes up when matching the
parameters of a template template parameter against the parameters of a
template template argument.)
The matching rules here are murky at best. Our behavior after this revert is
definitely wrong for certain C++17 features (for 'auto' template parameter
types within the parameter list of a template template argument in particular),
but our behavior before this revert is wrong for some pre-existing testcases,
so reverting to our prior behavior seems like our best option.
llvm-svn: 300262
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 73a6854..f522e76 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -2109,7 +2109,6 @@
typedef RecursiveASTVisitor<DependencyChecker> super;
unsigned Depth;
- bool FindLessThanDepth;
// Whether we're looking for a use of a template parameter that makes the
// overall construct type-dependent / a dependent type. This is strictly
@@ -2120,16 +2119,25 @@
bool Match;
SourceLocation MatchLoc;
- DependencyChecker(unsigned Depth, bool IgnoreNonTypeDependent,
- bool FindLessThanDepth = false)
- : Depth(Depth), FindLessThanDepth(FindLessThanDepth),
- IgnoreNonTypeDependent(IgnoreNonTypeDependent), Match(false) {}
+ DependencyChecker(unsigned Depth, bool IgnoreNonTypeDependent)
+ : Depth(Depth), IgnoreNonTypeDependent(IgnoreNonTypeDependent),
+ Match(false) {}
DependencyChecker(TemplateParameterList *Params, bool IgnoreNonTypeDependent)
- : DependencyChecker(Params->getDepth(), IgnoreNonTypeDependent) {}
+ : IgnoreNonTypeDependent(IgnoreNonTypeDependent), Match(false) {
+ NamedDecl *ND = Params->getParam(0);
+ if (TemplateTypeParmDecl *PD = dyn_cast<TemplateTypeParmDecl>(ND)) {
+ Depth = PD->getDepth();
+ } else if (NonTypeTemplateParmDecl *PD =
+ dyn_cast<NonTypeTemplateParmDecl>(ND)) {
+ Depth = PD->getDepth();
+ } else {
+ Depth = cast<TemplateTemplateParmDecl>(ND)->getDepth();
+ }
+ }
bool Matches(unsigned ParmDepth, SourceLocation Loc = SourceLocation()) {
- if (FindLessThanDepth ^ (ParmDepth >= Depth)) {
+ if (ParmDepth >= Depth) {
Match = true;
MatchLoc = Loc;
return true;
@@ -6432,15 +6440,6 @@
return E;
}
-static bool isDependentOnOuter(NonTypeTemplateParmDecl *NTTP) {
- if (NTTP->getDepth() == 0 || !NTTP->getType()->isDependentType())
- return false;
- DependencyChecker Checker(NTTP->getDepth(), /*IgnoreNonTypeDependent*/ false,
- /*FindLessThanDepth*/ true);
- Checker.TraverseType(NTTP->getType());
- return Checker.Match;
-}
-
/// \brief Match two template parameters within template parameter lists.
static bool MatchTemplateParameterKind(Sema &S, NamedDecl *New, NamedDecl *Old,
bool Complain,
@@ -6497,10 +6496,11 @@
// If we are matching a template template argument to a template
// template parameter and one of the non-type template parameter types
- // is dependent on an outer template's parameter, then we must wait until
- // template instantiation time to actually compare the arguments.
+ // is dependent, then we must wait until template instantiation time
+ // to actually compare the arguments.
if (Kind == Sema::TPL_TemplateTemplateArgumentMatch &&
- (isDependentOnOuter(OldNTTP) || isDependentOnOuter(NewNTTP)))
+ (OldNTTP->getType()->isDependentType() ||
+ NewNTTP->getType()->isDependentType()))
return true;
if (!S.Context.hasSameType(OldNTTP->getType(), NewNTTP->getType())) {