[Bug middle-end/92825] Unnecesary stack protection in Firefox's LightPixel.

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92825

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Tue Dec 10 21:04:08 2019
New Revision: 279193

URL: https://gcc.gnu.org/viewcvs?rev=279193&root=gcc&view=rev
Log:
        PR middle-end/92825
        * cfgexpand.c (add_stack_protection_conflicts): Change return type
        from void to bool, return true if at least one stack_vars[i].decl
        is addressable.
        (record_or_union_type_has_array_p, stack_protect_decl_p): Remove.
        (expand_used_vars): Don't call stack_protect_decl_p, instead for
        -fstack-protector-strong set gen_stack_protect_signal to true
        if add_stack_protection_conflicts returned true.  Formatting fixes.
        * doc/invoke.texi (-fstack-protector-strong): Clarify that optimized
        out variables or variables not living on the stack don't count.
        (-fstack-protector): Likewise.  Clarify it affects >= 8 byte arrays
        rather than > 8 byte.

        * gcc.target/i386/pr92825.c: New test.

Added:
    trunk/gcc/testsuite/gcc.target/i386/pr92825.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cfgexpand.c
    trunk/gcc/doc/invoke.texi
    trunk/gcc/testsuite/ChangeLog