https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114580
--- Comment #2 from GCC 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:cfed80b9e4f562c99679739548df9369117dd791 commit r14-9861-gcfed80b9e4f562c99679739548df9369117dd791 Author: Jakub Jelinek <ja...@redhat.com> Date: Tue Apr 9 09:31:42 2024 +0200 c++: Fix up maybe_warn_for_constant_evaluated calls [PR114580] When looking at maybe_warn_for_constant_evaluated for the trivial infinite loops patch, I've noticed that it can emit weird diagnostics for if constexpr in templates, first warn that std::is_constant_evaluted() always evaluates to false (because the function template is not constexpr) and then during instantiation warn that std::is_constant_evaluted() always evaluates to true (because it is used in if constexpr condition). Now, only the latter is actually true, even when the if constexpr is in a non-constexpr function, it will still always evaluate to true. So, the following patch fixes it to call maybe_warn_for_constant_evaluated always with IF_STMT_CONSTEXPR_P (if_stmt) as the second argument rather than true if it is if constexpr with non-dependent condition etc. 2024-04-09 Jakub Jelinek <ja...@redhat.com> PR c++/114580 * semantics.cc (finish_if_stmt_cond): Call maybe_warn_for_constant_evaluated with IF_STMT_CONSTEXPR_P (if_stmt) as the second argument, rather than true/false depending on if it is if constexpr with non-dependent constant expression with bool type. * g++.dg/cpp2a/is-constant-evaluated15.C: New test.
