Description:
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In my CI, I've noticed the test failing more and more often. When I've checked, the user that runs the builds had 700+ shared memory segments allocated. It appears that the test above doesn't release the segments it allocates, so at each run, "ipcs -m" reports 2-3 more segments.

Test script:
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php run-tests.php ext/shmop/tests/002.phpt > /dev/null; ipcs -m | grep 0x | wc -l
php run-tests.php ext/shmop/tests/002.phpt > /dev/null; ipcs -m | grep 0x | wc -l


Expected result:
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0
0

Actual result:
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3
5