[Bug libstdc++/117210] [15 regression] error: 'llabs' is not a member of 'std'; did you mean 'labs'

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117210

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Maybe we just need to include sys/cdefs.h in os_defines.h