compat/bswap.h: don't assume MSVC is little-endian

In 1af265f0 (compat/bswap.h: simplify MSVC endianness
detection, 2020-11-08) we attempted to simplify code by assuming MSVC
builds will be for little-endian machines, since only unusably old
versions of MSVC supported big-endian MIPS and m68k architectures.

However, it's possible that MSVC could be ported to build for a
big-endian architecture again, so the simplification wasn't as
future-proof as hoped.

So let's go back to the old way of detecting MSVC, and then checking
architecture from a list of little-endian architecture macros.

Note that MSVC does not treat ARM64 as bi-endian, so we can safely treat
it as little-endian.

Helped-by: brian m. carlson <>
Helped-by: Jeff King <>
Helped-by: Johannes Schindelin <>
Helped-by: Junio C Hamano <>
Signed-off-by: Daniel Gurney <>
Signed-off-by: Junio C Hamano <>
Daniel Gurney 2 years ago committed by Junio C Hamano
parent 1af265f0a0
commit 0c038fc65a
  1. 2

@ -74,7 +74,7 @@ static inline uint64_t git_bswap64(uint64_t x)
#elif defined(_MSC_VER)
#elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64) || defined(_M_ARM64))
#include <stdlib.h>