[Sema] Diagnose default argument on a parameter pack.
This is ill-formed (and cannot be used anyways).
PR23028.
llvm-svn: 233376
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index f7183bc..bb7ba94 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -316,8 +316,17 @@
if (DiagnoseUnexpandedParameterPack(DefaultArg, UPPC_DefaultArgument)) {
Param->setInvalidDecl();
return;
- }
-
+ }
+
+ // C++11 [dcl.fct.default]p3
+ // A default argument expression [...] shall not be specified for a
+ // parameter pack.
+ if (Param->isParameterPack()) {
+ Diag(EqualLoc, diag::err_param_default_argument_on_parameter_pack)
+ << DefaultArg->getSourceRange();
+ return;
+ }
+
// Check that the default argument is well-formed
CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg, this);
if (DefaultArgChecker.Visit(DefaultArg)) {