gnu/155309: [PATCH] gcc: backport bswap32() and bswap64()

[Bruce Evans]

On Sun, 6 Mar 2011, Martin Matuska wrote:

>> Description:
> In many ports, we have to deal with patching the missing bswap32()
> and bswap64() functions.

Er, we have these in endian.h.

> The gcc-4.3 branch SVN revision is 118361, is GPLv2-licensed,
> applies cleanly and is fully compatible with our code.

However, gcc doesn't know how to turn a C expression for bswap*() into
the bswap instruction.  clang does.  Does this patch fix that?  Using
the C expression in all cases allows cleaning endian.h files, except
possibly on other arches that still need asm.

Bruce