https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118605
--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-14 branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:7a369b6a5589c7d9187701ee916f939307e00a86 commit r14-11287-g7a369b6a5589c7d9187701ee916f939307e00a86 Author: Jakub Jelinek <ja...@redhat.com> Date: Thu Jan 23 11:46:18 2025 +0100 tree-assume: Fix UB in assume_query [PR118605] The assume_query constructor does assume_query::assume_query (function *f, bitmap p) : m_parm_list (p), m_func (f) where m_parm_list is bitmap &. This is compile time UB, because as soon as the constructor returns, m_parm_list reference is still bound to the parameter of the constructor which is no longer in scope. Now, one possible fix would be change the ctor argument to be bitmap &, but that doesn't really work because in the only user of that class we have auto_bitmap decls; ... assume_query query (fun, decls); and auto_bitmap just has operator bitmap () { return &m_bits; } Could be perhaps const bitmap &, but why? bitmap is a pointer: typedef class bitmap_head *bitmap; and the EXECUTE_IF_SET_IN_BITMAP macros don't really change that point, they just inspect what is inside of that bitmap_head the pointer points to. So, the simplest I think is avoid references (which cause even worse code as it has to be dereferenced twice rather than once). 2025-01-23 Jakub Jelinek <ja...@redhat.com> PR tree-optimization/118605 * tree-assume.cc (assume_query::m_parm_list): Change type from bitmap & to bitmap. (cherry picked from commit 27a05f8d11798889ecfb610db9bde781c3d218f7)
