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Re: general protection faults with "git grep" version 1.7.7.1

From
Jim Meyering <jim@meyering.net>
Date
Oct 25, 2011, 16:37 UTC
Message-ID
<87sjmhauyo.fsf@rho.meyering.net>
In-Reply-To
<201110251800.28054.trast@student.ethz.ch>
Thomas Rast wrote:
Show 10 quoted lines
> Jim Meyering wrote:
>> Thomas Rast wrote:
>> > [GCC moves access to a file-static variable across pthread_mutex_lock()]
>>
>> Thanks for the investigation.
>> Actually, isn't gcc -O2's code-motion justified?
>> While we *know* that those globals may be modified asynchronously,
>> builtin/grep.c forgot to tell gcc about that.
>
> I'm somewhat unwilling to believe that:

You're right to be skeptical. I should have stuck with "using volatile works around the problem for me". The real problem seems to be in glibc, with its addition of the "leaf" attribute to those synchronization primitives:

  http://bugzilla.redhat.com/747377#c22
Previous: Thomas RastNext: Thomas Rast
Message 12 of 15 in “general protection faults with "git grep" version 1.7.7.1”
  1. Markus TrippelsdorfOct 24, 2011
  2. Richard W.M. JonesOct 24, 2011
  3. Markus TrippelsdorfOct 24, 2011
  4. Bernt HansenOct 25, 2011
  5. Jeff KingOct 25, 2011
  6. Bernt HansenOct 25, 2011
  7. Thomas RastOct 25, 2011
  8. Jim MeyeringOct 25, 2011
  9. Markus TrippelsdorfOct 25, 2011
  10. Thomas RastOct 25, 2011
  11. Thomas RastOct 25, 2011
  12. Jim MeyeringOct 25, 2011
  13. Thomas RastOct 25, 2011
  14. Jim MeyeringOct 25, 2011
  15. Jeff KingOct 25, 2011

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