https://gcc.gnu.org/bugzilla/show_bug.cgi?id=20785
--- Comment #15 from Vincent Lefèvre <vincent-gcc at vinc17 dot net> --- (In reply to Pavel M from comment #14) > The "warning: ignoring '#pragma STDC FENV_ACCESS' [-Wunknown-pragmas]" > probably needs to be generated by default Getting the warning on "#pragma STDC FENV_ACCESS OFF" is useless. The issue comes from the fact that the FENV_ACCESS is OFF by default and you want to set it to ON; there should be a warning in this case, but only in this case. Concerning the other pragmas, this also depends on their default state. For instance, since commit 6dbe09581a1349498f6b4546f68cb9fd3205e120[*], the STDC FP_CONTRACT pragma is set to OFF by default when a standard mode is provided (e.g. -std=c17), so that the warning on this pragma is not needed in this case (whether the user sets it to ON or OFF). [*] https://gcc.gnu.org/git/?p=gcc.git&a=commit;h=6dbe09581a1349498f6b4546f68cb9fd3205e120
