https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63831
--- Comment #14 from Iain Sandoe <iains at gcc dot gnu.org> ---
this might be a hint:
<broken> c.f. <OK - __has_attribute cppdefine commented out>
$ diff -W200 -y --suppress-common-lines s-oscons-tmplt.i
/GCC/ml/gcc-trunk-apple/gcc/ada/rts/s-oscons-tmplt.i
# 102 "/GCC/ml/gcc-trunk-bust/./gcc/include-fixed/limits.h" 3 4
| # 102
"/GCC/ml/gcc-trunk-apple/./gcc/include-fixed/limits.h" 3 4
/* make sure a default max version is set */__has_attribute__
(availability) | /* make sure a default max version is
set */
# 1 "/GCC/ml/gcc-trunk-bust/./gcc/include/stdint.h" 1 3 4
| # 1 "/GCC/ml/gcc-trunk-apple/./gcc/include/stdint.h" 1
3 4
