https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63765
--- Comment #11 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot
Uni-Bielefeld.DE> ---
> --- Comment #9 from David Edelsohn <dje at gcc dot gnu.org> ---
> I would have expected _XOPEN_SOURCE=500 to be defined in a host-specific
> configure file (like libstdc++-v3/config/os/.../os_defines.h) or added to the
> compile line in configure.
Given how little target-specific configuration libobjc needs, this seems
overkill to me.
Rainer
