On Tue, Apr 3, 2018 at 9:08 AM Jakub Jelinek <[email protected]> wrote:
> As mentioned in the PR, GCC (and clang) predefines
> {__BYTE_ORDER__,__ORDER_{LITTLE,BIG,PDP}_ENDIAN__}
> macros, and {,sys/,machine/}endian.h headers predefine
> {,__}{BYTE_ORDER,{LITTLE,BIG,PDP}_ENDIAN}
> macros (depending on which target and feature test macros).
> elf.c in GCC 8 used __BYTE_ORDER, which is endian.h macro, but
> didn't include that header and it on glibc just happened to be included
> indirectly because of default feature test macros from stdlib.h,
> and used non-existing __ORDER_BIG_ENDIAN macro; as __BYTE_ORDER is always
> non-zero when defined (1234, 4321 etc.), that means __builtin_bswap32
> was never used.
> The following patch just uses the GCC/clang predefined macros if known to
be
> big or little endian, and otherwise just falls back to portable code (that
> good compilers can still optimize).
> Bootstrapped/regtested on x86_64-linux and i686-linux and tested on
> powerpc64-linux, ok for trunk?
> 2018-04-03 Jakub Jelinek <[email protected]>
> PR other/85161
> * elf.c (elf_zlib_fetch): Fix up predefined macro names in test
for
> big endian, only use 32-bit loads if endianity macros are
predefined
> and indicate big or little endian.
This is OK. Thanks for sorting that out.
Ian
