k...@munnari.oz.au (Robert Elz) writes: >(there are some standardised <sys/foo.h> headers, but <sys/endian.h> >is not one of them). Tools should not be including non-standard headers.
On the other hand <endian.h> is a late addition (from 2017) and MacOS doesn't follow the standard. You probably need: #if defined(__APPLE__) #include <machine/endian.h> #endif