devel/apr bug #51851

[Alexander Nasonov <alnsn%yandex.ru@localhost>]

One of my colleagues was hit by this bug:
https://issues.apache.org/bugzilla/show_bug.cgi?id=51851

I can't reproduce it on -current amd64 with gcc3 even with a patched
testatomic.c but I see a different assembly.

Original:
00000000000000a0 <apr_atomic_xchgptr>:
  a0:   48 87 37                xchg   %rsi,(%rdi)
  a3:   c3                      retq   

Patched:
00000000000000a0 <apr_atomic_xchgptr>:
  a0:   48 89 f0                mov    %rsi,%rax
  a3:   48 87 07                xchg   %rax,(%rdi)
  a6:   c3                      retq   

Original doesn't look right.

I'm like to add the patch if there are no objections.
Thanks,
Alex