c++: Fix default argument parsing in non-comma variadic methods [PR121539]

While the non-comma variadic functions/methods were deprecated in C++26,
they are still valid and they are valid without deprecation in C++98 to
C++23.
We parse default arguments followed by ...) outside of classes or
for out of class definitions of methods, but I think since C++11 support
in GCC 4.9 or so we consider ... to be a part of a default argument and
error on it.
I think a default argument can't validly contain a pack expansion
that ends the expression with ..., so I think we can simply handle
...) if at depth 0 as not part of the default argument.

2025-08-15  Jakub Jelinek  <jakub@redhat.com>

	PR c++/121539
	* parser.cc (cp_parser_cache_defarg): Set done to true for
	CPP_ELLIPSIS followed by CPP_CLOSE_PAREN in !nsdmi at depth 0.

	* g++.dg/parse/defarg20.C: New test.

0 files changed, 0 insertions, 0 deletions