[Bug target/79462] [7 Regression] sh: Stack smashing detected when building __ashrdi3 in libgcc

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79462

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |jakub at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 40718
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=40718&action=edit
gcc7-pr79462.patch

Untested fix.  I believe the bug has been introduced in r235698 aka PR52898
fix, when the clobbers have been removed from expanders calling
expand_cbranchdi4.  operands[4] used to be that clobber, but now when it has
only 4 operands, it overwrites random memory after it.
I don't have access to SH hw nor any experience with cross-compilers to SH, so
I'd appreciate if somebody could actually test it.