Fast-path an arity check when performing template argument deduction that compares two parameter-type-lists. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@122928 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaTemplateDeduction.cpp b/lib/Sema/SemaTemplateDeduction.cpp
index e762d34..603a7ef 100644
--- a/lib/Sema/SemaTemplateDeduction.cpp
+++ b/lib/Sema/SemaTemplateDeduction.cpp
@@ -541,8 +541,12 @@
TemplateDeductionInfo &Info,
llvm::SmallVectorImpl<DeducedTemplateArgument> &Deduced,
unsigned TDF) {
- // FIXME: Fast-path check with NumParams != NumArgs and there are no
- // pack expansions around.
+ // Fast-path check to see if we have too many/too few arguments.
+ if (NumParams != NumArgs &&
+ !(NumParams && isa<PackExpansionType>(Params[NumParams - 1])) &&
+ !(NumArgs && isa<PackExpansionType>(Args[NumArgs - 1])))
+ return NumArgs < NumParams ? Sema::TDK_TooFewArguments
+ : Sema::TDK_TooManyArguments;
// C++0x [temp.deduct.type]p10:
// Similarly, if P has a form that contains (T), then each parameter type