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2019-10-17move __BYTE_ORDER definition to alltypes.hRich Felker-5/+0
this change is motivated by the intersection of several factors. presently, despite being a nonstandard header, endian.h is exposing the unprefixed byte order macros and functions only if _BSD_SOURCE or _GNU_SOURCE is defined. this is to accommodate use of endian.h from other headers, including bits headers, which need to define structure layout in terms of endianness. with time64 switch-over, even more headers will need to do this. at the same time, the resolution of Austin Group issue 162 makes endian.h a standard header for POSIX-future, requiring that it expose the unprefixed macros and the functions even in standards-conforming profiles. changes to meet this new requirement would break existing internal usage of endian.h by causing it to violate namespace where it's used. instead, have the arch's alltypes.h define __BYTE_ORDER, either as a fixed constant or depending on the right arch-specific predefined macros for determining endianness. explicit literals 1234 and 4321 are used instead of __LITTLE_ENDIAN and __BIG_ENDIAN so that there's no danger of getting the wrong result if a macro is undefined and implicitly evaluates to 0 at the preprocessor level. the powerpc (32-bit) bits/endian.h being removed had logic for varying endianness, but our powerpc arch has never supported that and has always been big-endian-only. this logic is not carried over to the new __BYTE_ORDER definition in alltypes.h.
2012-10-18better support for reverse-endian variants of arm/mips/microblazeRich Felker-0/+4
these macros are supported by more compilers
2011-09-18initial commit of the arm portRich Felker-0/+1
this port assumes eabi calling conventions, eabi linux syscall convention, and presence of the kernel helpers at 0xffff0f?0 needed for threads support. otherwise it makes very few assumptions, and the code should work even on armv4 without thumb support, as well as on systems with thumb interworking. the bits headers declare this a little endian system, but as far as i can tell the code should work equally well on big endian. some small details are probably broken; so far, testing has been limited to qemu/aboriginal linux.