Implement more of C++0x [temp.arg.explicit]p9, allowing extension of
pack expansions in template argument lists and function parameter
lists. The implementation of this paragraph should be complete
*except* for cases where we're substituting into one of the unexpanded
packs in a pack expansion; that's a general issue I haven't solved yet.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@123188 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaTemplateDeduction.cpp b/lib/Sema/SemaTemplateDeduction.cpp
index 02e1a42..842ad5c 100644
--- a/lib/Sema/SemaTemplateDeduction.cpp
+++ b/lib/Sema/SemaTemplateDeduction.cpp
@@ -636,8 +636,7 @@
if (NumParams != NumArgs &&
!(NumParams && isa<PackExpansionType>(Params[NumParams - 1])) &&
!(NumArgs && isa<PackExpansionType>(Args[NumArgs - 1])))
- return NumArgs < NumParams ? Sema::TDK_TooFewArguments
- : Sema::TDK_TooManyArguments;
+ return Sema::TDK_NonDeducedMismatch;
// C++0x [temp.deduct.type]p10:
// Similarly, if P has a form that contains (T), then each parameter type
@@ -654,7 +653,7 @@
// Make sure we have an argument.
if (ArgIdx >= NumArgs)
- return Sema::TDK_TooFewArguments;
+ return Sema::TDK_NonDeducedMismatch;
if (Sema::TemplateDeductionResult Result
= DeduceTemplateArguments(S, TemplateParams,
@@ -736,7 +735,7 @@
// Make sure we don't have any extra arguments.
if (ArgIdx < NumArgs)
- return Sema::TDK_TooManyArguments;
+ return Sema::TDK_NonDeducedMismatch;
return Sema::TDK_Success;
}
@@ -788,10 +787,8 @@
// If the parameter type is not dependent, there is nothing to deduce.
if (!Param->isDependentType()) {
- if (!(TDF & TDF_SkipNonDependent) && Param != Arg) {
-
+ if (!(TDF & TDF_SkipNonDependent) && Param != Arg)
return Sema::TDK_NonDeducedMismatch;
- }
return Sema::TDK_Success;
}
@@ -1365,7 +1362,7 @@
// Check whether we have enough arguments.
if (!hasTemplateArgumentForDeduction(Args, ArgIdx, NumArgs))
- return NumberOfArgumentsMustMatch? Sema::TDK_TooFewArguments
+ return NumberOfArgumentsMustMatch? Sema::TDK_NonDeducedMismatch
: Sema::TDK_Success;
// Perform deduction for this Pi/Ai pair.
@@ -1459,7 +1456,7 @@
// If there is an argument remaining, then we had too many arguments.
if (NumberOfArgumentsMustMatch &&
hasTemplateArgumentForDeduction(Args, ArgIdx, NumArgs))
- return Sema::TDK_TooManyArguments;
+ return Sema::TDK_NonDeducedMismatch;
return Sema::TDK_Success;
}
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index 7eee444..bc1ac1e 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -2850,7 +2850,20 @@
Outputs.addArgument(Out);
}
- // FIXME: Variadic templates retain expansion!
+ // If we're supposed to retain a pack expansion, do so by temporarily
+ // forgetting the partially-substituted parameter pack.
+ if (RetainExpansion) {
+ ForgetPartiallySubstitutedPackRAII Forget(getDerived());
+
+ if (getDerived().TransformTemplateArgument(Pattern, Out))
+ return true;
+
+ Out = getDerived().RebuildPackExpansion(Out, Ellipsis);
+ if (Out.getArgument().isNull())
+ return true;
+
+ Outputs.addArgument(Out);
+ }
continue;
}
@@ -3564,7 +3577,18 @@
continue;
}
- // FIXME: Variadic templates retain pack expansion!
+ // If we're supposed to retain a pack expansion, do so by temporarily
+ // forgetting the partially-substituted parameter pack.
+ if (RetainExpansion) {
+ ForgetPartiallySubstitutedPackRAII Forget(getDerived());
+ QualType NewType = getDerived().TransformType(Pattern);
+ if (NewType.isNull())
+ return true;
+
+ OutParamTypes.push_back(NewType);
+ if (PVars)
+ PVars->push_back(0);
+ }
// We'll substitute the parameter now without expanding the pack
// expansion.