PR preprocessor/83063 - __VA_OPT__ and ##
PR preprocessor/83708
* macro.c (vaopt_state): Reorder m_last_was_paste before m_state.
(vaopt_state::vaopt_state): Adjust.
(vaopt_state::update_flags): Add BEGIN and END.
(vaopt_state::update): Return them.
(copy_paste_flag): Factor out of replace_args.
(last_token_is): New.
(replace_args): Handle BEGIN and END. Avoid padding there.
(tokens_buff_last_token_ptr): Return NULL if no tokens.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@257696 138bc75d-0d04-0410-961f-82ee72b054a4