https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78468
--- Comment #39 from Eric Botcazou <ebotcazou at gcc dot gnu.org> --- > The existing alloca code relies on STACK_BOUNDARY being set correctly. Has > the value been fixed already for the OS variants mentioned? If stack > alignment can't be guaranteed by OS/runtime/prolog, STACK_BOUNDARY should be > 8. No, no, no, please read the ??? note I put in emit-rtl.c. STACK_BOUNDARY is correct, the problem is the declared alignment of the virtual registers.
