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STC for libapr1 failure

The libapr1 test cases are failing again for flock locks. This same
test case failed with 1.7.9 with a fatal error[1], but that was
corrected. The test is no longer encountering the fatal error, but
it is producing the wrong result.

I extracted the attached STC to demonstrate the problem. It starts a
number of child processes, each of which repeatedly grab and release
a lock on a temporary file. While they have the lock, the increment
a counter in shared memory in a racy way.

If all goes well, the counter should end up having the value of
CHILDREN * ITERS_PER_CHILDREN. And it does, sometimes. Other times,
however, it's less than this value, indicating the lock did not

(I'm using shmget for shared memory, so you have to have cygserver
running. APR has a number of shared memory methods, including mmap,
but this was the easiest for me to extract.)

As before, I haven't been doing C programming in a while, so I'm not
100% sure the test case is valid, but it does demonstrate the same
problem the APR test case is having.

I've tried this on my Win7-64 box running the 20120210 snapshot and
on a WinXP running stock 1.7.10. I get the same results in both



David Rothenberger  ----

I think we are in Rats' Alley where the dead men lost their bones.
                -- T.S. Eliot

Attachment: stc-flock-fork.c
Description: Text document

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