In curlbuild.h, the non-configure generic GCC fallback is dubious:

# if defined(__ILP32__) || \
      defined(__i386__) || defined(__ppc__) || defined(__arm__) || \
      defined(__sparc__) || defined(__mips__) || defined(__sh__)
...
# elif defined(__LP64__) || \
        defined(__x86_64__) || defined(__ppc64__) || defined(__sparc64__)
...

On sparc64, gcc defines both __sparc64__ and __sparc__, so the code
above will pick the wrong definitions. Same for __mips64__ and
__mips__ on mips64 platforms. I don't know about ppc64.

An easy fix would be to exchange the order, i.e., check for __LP64__
first.

(I don't use this non-configure code in any way, I just happened to
notice.)

-- 
Christian "naddy" Weisgerber                          naddy_at_mips.inka.de
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