https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118199
--- Comment #19 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Simon Martin <simar...@gcc.gnu.org>: https://gcc.gnu.org/g:e13e751d8144c9cfb7a9f1cd38119d1fa4ab38cf commit r15-7122-ge13e751d8144c9cfb7a9f1cd38119d1fa4ab38cf Author: Simon Martin <si...@nasilyan.com> Date: Wed Jan 22 10:44:32 2025 +0100 c++: Clear TARGET_EXPR_ELIDING_P when forced to use a copy constructor due to __no_unique_address__ [PR118199] We currently fail with a checking assert upon the following valid code when using -fno-elide-constructors === cut here === struct d { ~d(); }; d &b(); struct f { [[__no_unique_address__]] d e; }; struct h : f { h() : f{b()} {} } i; === cut here === The problem is that split_nonconstant_init_1 detects that it cannot elide the copy constructor due to __no_unique_address__ but does not clear TARGET_EXPR_ELIDING_P, and due to -fno-elide-constructors, we trip on a checking assert in cp_gimplify_expr. This patch fixes this by making sure that we clear TARGET_EXPR_ELIDING_P if we determine that we have to keep the copy constructor due to __no_unique_address__. An alternative would be to just check for elide_constructors in that assert, but I think it'd lose most of its value if we did so. PR c++/118199 gcc/cp/ChangeLog: * typeck2.cc (split_nonconstant_init_1): Clear TARGET_EXPR_ELIDING_P if we need to use a copy constructor because of __no_unique_address__. gcc/testsuite/ChangeLog: * g++.dg/init/no-elide3.C: New test.
