[Bug tree-optimization/83412] GCC line directive suppresses warnings

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83412

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
# 12 "a.c" 3 4

This means you are in a system header so -Wsystem is needed IIRC.