https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106760
--- 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:79c5a09f959dc63824bd005522a072424f16d89d commit r14-10449-g79c5a09f959dc63824bd005522a072424f16d89d Author: Patrick Palka <ppa...@redhat.com> Date: Fri Jun 28 19:45:21 2024 -0400 c++: bad 'this' conversion for nullary memfn [PR106760] Here we notice the 'this' conversion for the call f<void>() is bad, so we correctly defer deduction for the template candidate, but we end up never adding it to 'bad_cands' since missing_conversion_p for it returns false (its only argument is 'this' which has already been determined to be bad). This is not a huge deal, but it causes us to longer accept the call with -fpermissive in release builds, and a tree check ICE in checking builds. So if we have a non-strictly viable template candidate that has not been instantiated, then we need to add it to 'bad_cands' even if no argument conversion is missing. PR c++/106760 gcc/cp/ChangeLog: * call.cc (add_candidates): Relax test for adding a candidate to 'bad_cands' to also accept an uninstantiated template candidate that has no missing conversions. gcc/testsuite/ChangeLog: * g++.dg/ext/conv3.C: New test. Reviewed-by: Jason Merrill <ja...@redhat.com> (cherry picked from commit 50073ffae0a9b8feb9b36fdafdebd9885f6d7dc8)
