[Bug tree-optimization/78482] [5/6/7 Regression] wrong code at -O3 in both 32-bit and 64-bit modes on x86_64-linux-gnu

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78482

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 40135
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=40135&action=edit
gcc7-pr78482-test.patch

Does this patch fix that?

In addition to changing char to signed char, I've changed the testcase so that
it actually FAILs with unfixed compiler and PASSes with fixed one, previously
with unfixed compiler it would just print 2 on stdout where nothing would
notice that.