[Bug libfortran/51119] MATMUL slow for large matrices

[jb at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51119

--- Comment #43 from Janne Blomqvist <jb at gcc dot gnu.org> ---
Compile warnings caused by this patch:

cc1: warning: command line option ‘-fno-protect-parens’ is valid for Fortran
but not for C
cc1: warning: command line option ‘-fstack-arrays’ is valid for Fortran but not
for C