Fix template argument deduction when a parameter pack has a value
provided by an outer template.
We made the incorrect assumption in various places that the only way we
can have any arguments already provided for a pack during template
argument deduction was from a partially-specified pack. That's not true;
we can also have arguments from an enclosing already-instantiated
template, and that can even result in the function template's own pack
parameters having a fixed length and not being packs for the purposes of
template argument deduction.
llvm-svn: 337481
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index 35c3612..822c3c0 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -629,6 +629,8 @@
break;
}
+ case Sema::TDK_IncompletePack:
+ // FIXME: It's slightly wasteful to allocate two TemplateArguments for this.
case Sema::TDK_Inconsistent:
case Sema::TDK_Underqualified: {
// FIXME: Should allocate from normal heap so that we can free this later.
@@ -671,6 +673,7 @@
case Sema::TDK_NonDependentConversionFailure:
break;
+ case Sema::TDK_IncompletePack:
case Sema::TDK_Inconsistent:
case Sema::TDK_Underqualified:
case Sema::TDK_DeducedMismatch:
@@ -720,6 +723,7 @@
case Sema::TDK_InvalidExplicitArguments:
return TemplateParameter::getFromOpaqueValue(Data);
+ case Sema::TDK_IncompletePack:
case Sema::TDK_Inconsistent:
case Sema::TDK_Underqualified:
return static_cast<DFIParamWithArguments*>(Data)->Param;
@@ -740,6 +744,7 @@
case Sema::TDK_TooManyArguments:
case Sema::TDK_TooFewArguments:
case Sema::TDK_Incomplete:
+ case Sema::TDK_IncompletePack:
case Sema::TDK_InvalidExplicitArguments:
case Sema::TDK_Inconsistent:
case Sema::TDK_Underqualified:
@@ -777,6 +782,7 @@
case Sema::TDK_NonDependentConversionFailure:
return nullptr;
+ case Sema::TDK_IncompletePack:
case Sema::TDK_Inconsistent:
case Sema::TDK_Underqualified:
case Sema::TDK_DeducedMismatch:
@@ -798,6 +804,7 @@
case Sema::TDK_Invalid:
case Sema::TDK_InstantiationDepth:
case Sema::TDK_Incomplete:
+ case Sema::TDK_IncompletePack:
case Sema::TDK_TooManyArguments:
case Sema::TDK_TooFewArguments:
case Sema::TDK_InvalidExplicitArguments:
@@ -9893,6 +9900,17 @@
return;
}
+ case Sema::TDK_IncompletePack: {
+ assert(ParamD && "no parameter found for incomplete deduction result");
+ S.Diag(Templated->getLocation(),
+ diag::note_ovl_candidate_incomplete_deduction_pack)
+ << ParamD->getDeclName()
+ << (DeductionFailure.getFirstArg()->pack_size() + 1)
+ << *DeductionFailure.getFirstArg();
+ MaybeEmitInheritedConstructorNote(S, Found);
+ return;
+ }
+
case Sema::TDK_Underqualified: {
assert(ParamD && "no parameter found for bad qualifiers deduction result");
TemplateTypeParmDecl *TParam = cast<TemplateTypeParmDecl>(ParamD);
@@ -10372,6 +10390,7 @@
case Sema::TDK_Invalid:
case Sema::TDK_Incomplete:
+ case Sema::TDK_IncompletePack:
return 1;
case Sema::TDK_Underqualified: