* Junio C Hamano <gits...@pobox.com> [170627 13:38]: > "Liam R. Howlett" <liam.howl...@oracle.com> writes: > > > How about: > > > > ---- 8< ---- > > diff --git a/sha1dc/sha1.c b/sha1dc/sha1.c > > index facea1bb5..ed8c63f2d 100644 > > --- a/sha1dc/sha1.c > > +++ b/sha1dc/sha1.c > > @@ -38,9 +38,18 @@ > > > > #if (defined(_BYTE_ORDER) || defined(__BYTE_ORDER) || > > defined(__BYTE_ORDER__)) > > > > +#define EMPTY_VAL(x) x ## 1 > > +#define EMPTY(x) EMPTY_VAL(x) > > + > > +#if (defined(_BIG_ENDIAN) && (EMPTY(_BIG_ENDIAN) == 1)) > > +#undef _BIG_ENDIAN > > +#define _BIG_ENDIAN 4321 > > +#endif > > I'd say it is a bad idea to define a symbol that you _know_ a > platform header file defines. Any header you may include from the > platform after these lines still expects the symbol to be defined in > a way it defines without getting molested and will misbehave.
Okay. Thanks. I thought a c file would be safe, especially after the includes but there is indeed a possible include (ifdef'ed) later. This compressed logic is causing a lot of issues. Could we just rewrite it as a whole lot of #if/#else, statements to avoid running across the issue where the precompiler does not short-circuit the checks? Would this cause any other issues? Alternatively, we can replace the undef/define with the define of SHA1DC_BIGENDIAN and make this an #if/#else.. A third option is to compile a small test and just -DSHA1DC_BIGENDIAN in the Makefile. Cheers, Liam
