https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100666
--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:ad52d89808a947264397e920d7483090d4108f7b commit r12-1043-gad52d89808a947264397e920d7483090d4108f7b Author: Jakub Jelinek <ja...@redhat.com> Date: Tue May 25 17:24:38 2021 +0200 c++: Avoid -Wunused-value false positives on nullptr passed to ellipsis [PR100666] When passing expressions with decltype(nullptr) type with side-effects to ellipsis, we pass (void *)0 instead, but for the side-effects evaluate them on the lhs of a COMPOUND_EXPR. Unfortunately that means we warn about it if the expression is a call to nodiscard marked function, even when the result is really used, just needs to be transformed. Fixed by adding a warning_sentinel. 2021-05-25 Jakub Jelinek <ja...@redhat.com> PR c++/100666 * call.c (convert_arg_to_ellipsis): For expressions with NULLPTR_TYPE and side-effects, temporarily disable -Wunused-result warning when building COMPOUND_EXPR. * g++.dg/cpp1z/nodiscard8.C: New test. * g++.dg/cpp1z/nodiscard9.C: New test.
