Re: tr/xdiff-fast-hash generates warnings and breaks tests

From: René Scharfe <rene.scharfe@lsrfire.ath.cx>
Date: May 17, 2012, 07:11 UTC
Message-ID: <4FB4A4B9.3080009@lsrfire.ath.cx>
In-Reply-To: <CAA787r=WCJXeDipiVL37oMgji=ncoPyXXVOcCyYbSC6iCcTi1g@mail.gmail.com>

Am 17.05.2012 01:31, schrieb Øyvind A. Holm:

> On Debian GNU/Linux 6.0.5 (squeeze), the two commits on the
> tr/xdiff-fast-hash branch introduces compiler warnings and breaks
> t/t0020-crlf.sh and maybe later tests:

What does the following short C program report when run (e.g. put it in a file named s.c, then run "gcc -o s s.c" and "./s")?

   #include <stdio.h>
   int main(int argc, const char **argv) {
     printf("%u %u %u\n", sizeof(int), sizeof(long), sizeof(void *));
     return 0;
   }

I suspect you run a 32-bit userland on a 64-bit kernel.

On Ubuntu 12.04 x86, t0020 fails for me as well when I compile with XDL_FAST_HASH explicitly set (it's off by default). It succeeds after reverting 6f1af02, though, strangely enough. No compiler warnings are printed in either case.

   $ gcc --version
   gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3

   $ uname -a
   Linux ubuntu 3.2.0-24-generic #37-Ubuntu SMP Wed Apr 25 08:43:52 UTC 
2012 i686 i686 i386 GNU/Linux

Also, here are the measurements for master (v1.7.10.2-520-g6a4a482) without XDL_FAST_HASH, and with master minus 6f1af02 plus explicitly set XDL_FAST_HASH:

   Test                                 master           reverted+FAST
   ---------------------------------------------------------------------
   4000.1: log -3000 (baseline)         0.08(0.05+0.02)  0.08(0.05+0.02)
   4000.2: log --raw -3000 (tree-only)  0.39(0.34+0.04)  0.39(0.32+0.06)
   4000.3: log -p -3000 (Myers)         1.55(1.43+0.11)  1.43(1.29+0.12)
   4000.4: log -p -3000 --histogram     1.63(1.51+0.10)  1.50(1.35+0.14)
   4000.5: log -p -3000 --patience      1.85(1.71+0.13)  1.73(1.62+0.10)

René