https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114275
--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Nathaniel Shead <nsh...@gcc.gnu.org>: https://gcc.gnu.org/g:ec2365e07537e8b17745d75c28a2b45bf33be119 commit r15-220-gec2365e07537e8b17745d75c28a2b45bf33be119 Author: Nathaniel Shead <nathanielosh...@gmail.com> Date: Fri May 3 19:36:17 2024 +1000 c++/modules: Fix dangling pointer with imported_temploid_friends I got notified by Linaro CI and by checking testresults that there seems to be some occasional failures in tpl-friend-4_b.C on some architectures and standards modes since r15-59-gb5f6a56940e708. I haven't been able to reproduce but looking at the backtrace I suspect the issue is that we're adding to the 'imported_temploid_friend' map a decl that is ultimately discarded, which then has its address reused by a later decl causing a failure in the assert in 'set_originating_module'. This patch fixes the problem by ensuring 'imported_temploid_friends' is correctly marked as a GTY root, and that 'duplicate_decls' properly removes entries from the map for declarations that it frees. PR c++/114275 gcc/cp/ChangeLog: * cp-tree.h (remove_defining_module): Declare. * decl.cc (duplicate_decls): Call remove_defining_module on to-be-freed newdecl. * module.cc (imported_temploid_friends): Mark as GTY root... (init_modules): ...and allocate from ggc. (trees_in::decl_value): Only track for declarations that won't be discarded. (remove_defining_module): New function. Signed-off-by: Nathaniel Shead <nathanielosh...@gmail.com> Reviewed-by: Jason Merrill <ja...@redhat.com> Reviewed-by: Patrick Palka <ppa...@redhat.com>
