hts_newthread() leaves the pthread attributes object undestroyed when thread creation fails#807
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xroche wants to merge 9 commits into
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hts_newthread() leaves the pthread attributes object undestroyed when thread creation fails#807xroche wants to merge 9 commits into
xroche wants to merge 9 commits into
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… thread creation fails hts_newthread() folds pthread_attr_init(), pthread_attr_setstacksize() and pthread_create() into one short-circuit condition, and destroys the attributes object only on the branch where all three succeeded. If setstacksize or create fails (EAGAIN under thread or memory exhaustion being the realistic case), attr stays initialised for good. glibc allocates nothing for a default-initialised attr, so nothing actually leaks on Linux. This is a portability and hygiene fix rather than a live bug. The init has to come out of the chain instead of just gaining a destroy call: the shared condition cannot tell which of the three failed, and destroying an object pthread_attr_init() never initialised is undefined. The imbalance is invisible to a leak checker, so the test counts it directly. A small LD_PRELOAD shim refuses pthread_create() and records which attributes objects nobody destroyed afterwards: 1 undestroyed on master, 0 with the fix. Closes #772 Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
Condense the two-line note above pthread_attr_init(), fix the "so that is can be independent" typo on the line the diff moves, and count a refused spawn as tested only when it carried an attributes object, so a NULL-attr create from elsewhere cannot satisfy the guard on its own. Note why the shim's fixed slot count and unlocked counters are enough. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
Resolve the tests/Makefile.am TESTS-tail conflict: keep both 111 and 113 entries in numeric order. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
Resolve the tests/Makefile.am TESTS-tail conflict: keep 110, 111 and 113 in numeric order. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
Fix the TESTS-tail union merge's missing continuation backslash. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
Register 113_engine-threadattr-leak.test in tests-list.mk after the #845 TESTS-list restructure moved it out of tests/Makefile.am, and keep this branch's libthreadattrfail build rules (EXTRA_DIST, TESTS_ENVIRONMENT, check_LTLIBRARIES, *_la_* rules) that a wholesale take-master resolution had dropped. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
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hts_newthread()foldspthread_attr_init(),pthread_attr_setstacksize()andpthread_create()into one short-circuit condition, and destroys the attributes object only on the branch where all three succeeded. If setstacksize or create fails (EAGAIN under thread or memory exhaustion being the realistic case),attrstays initialised for good. glibc allocates nothing for a default-initialised attr, so nothing actually leaks on Linux. This is a portability and hygiene fix rather than a live bug.The init has to come out of the chain instead of just gaining a destroy call: the shared condition cannot tell which of the three failed, and destroying an object
pthread_attr_init()never initialised is undefined.The imbalance is invisible to a leak checker, so the test counts it directly. A small LD_PRELOAD shim refuses
pthread_create()and records which attributes objects nobody destroyed afterwards: 1 undestroyed on master, 0 with the fix.Closes #772