[Bug tree-optimization/120138] (14/15/16) -Wmaybe-uninitialized triggered after specific optimizations

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120138

--- Comment #8 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
You could also add:
if (mrem <= 8) __builtin_unreachable();

to transpose_contiguous_16x2_block and that will fix the unitialized warning
too.