From 5545d1edcbdb1701443f94dde7ec97c5ce3e1a6c Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Thu, 30 Dec 2021 22:23:58 +0100 Subject: libcpp: Fix up ##__VA_OPT__ handling [PR89971] In the following testcase we incorrectly error about pasting / token with padding token (which is a result of __VA_OPT__); instead we should like e.g. for ##arg where arg is empty macro argument clear PASTE_LEFT flag of the previous token if __VA_OPT__ doesn't add any real tokens (which can happen either because the macro doesn't have any tokens passed to ... (i.e. __VA_ARGS__ expands to empty) or when __VA_OPT__ doesn't have any tokens in between ()s). 2021-12-30 Jakub Jelinek PR preprocessor/89971 libcpp/ * macro.c (replace_args): For ##__VA_OPT__, if __VA_OPT__ expands to no tokens at all, drop PASTE_LEFT flag from the previous token. gcc/testsuite/ * c-c++-common/cpp/va-opt-9.c: New test. --- libcpp/macro.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'libcpp/macro.c') diff --git a/libcpp/macro.c b/libcpp/macro.c index 6269c15..369383f 100644 --- a/libcpp/macro.c +++ b/libcpp/macro.c @@ -2094,8 +2094,14 @@ replace_args (cpp_reader *pfile, cpp_hashnode *node, cpp_macro *macro, tokens_buff_add_token (buff, virt_locs, t, t->src_loc, t->src_loc, NULL, 0); + continue; } - else if (src->flags & PASTE_LEFT) + if (start && paste_flag == start && (*start)->flags & PASTE_LEFT) + /* If __VA_OPT__ expands to nothing (either because __VA_ARGS__ + is empty or because it is __VA_OPT__() ), drop PASTE_LEFT + flag from previous token. */ + copy_paste_flag (pfile, start, &pfile->avoid_paste); + if (src->flags & PASTE_LEFT) { /* Don't avoid paste after all. */ while (paste_flag && paste_flag != start -- cgit v1.1