https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115239
--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-14 branch has been updated by Patrick Palka <ppa...@gcc.gnu.org>: https://gcc.gnu.org/g:4df86402990e2f45e02a367f1734a22ebc041e98 commit r14-10319-g4df86402990e2f45e02a367f1734a22ebc041e98 Author: Patrick Palka <ppa...@redhat.com> Date: Thu Jun 13 10:02:43 2024 -0400 c++: ICE w/ ambig and non-strictly-viable cands [PR115239] Here during overload resolution we have two strictly viable ambiguous candidates #1 and #2, and two non-strictly viable candidates #3 and #4 which we hold on to ever since r14-6522. These latter candidates have an empty second arg conversion since the first arg conversion was deemed bad, and this trips up joust when called on #3 and #4 which assumes all arg conversions are there. We can fix this by making joust robust to empty arg conversions, but in this situation we shouldn't need to compare #3 and #4 at all given that we have a strictly viable candidate. To that end, this patch makes tourney shortcut considering non-strictly viable candidates upon encountering ambiguity between two strictly viable candidates (taking advantage of the fact that the candidates list is sorted according to viability via splice_viable). PR c++/115239 gcc/cp/ChangeLog: * call.cc (tourney): Don't consider a non-strictly viable candidate as the champ if there was ambiguity between two strictly viable candidates. gcc/testsuite/ChangeLog: * g++.dg/overload/error7.C: New test. Reviewed-by: Jason Merrill <ja...@redhat.com> (cherry picked from commit 7fed7e9bbc57d502e141e079a6be2706bdbd4560)
