uk_init_tls: Initialize the TSD to the value expected by musl #82
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Even if the TSD has been initialized already, the first call to `pthread_create` will (re)set it to point to the statically-allocated `__pthread_tsd_main` (see (1)). So, before this patch, the memory allocated for the TSD leaked and, worse, the following sequence: ``` pthread_key_create(&key, NULL); pthread_setspecific(key, value); assert(pthread_getspecific(key) == value); pthread_create(&th, NULL, &thrd, NULL); assert(pthread_getspecific(key) == value); ``` ended up with the final assertion failing. (1) src/thread/pthread_create.c line 255 in musl v1.2.3 Signed-off-by: Samuel Hym <samuel@tarides.com>
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Even if the TSD has been initialized already, the first call to
pthread_createwill (re)set it to point to the statically-allocated__pthread_tsd_main(see (1)). So, before this patch, the memory allocated for the TSD leaked and, worse, the following sequence:ended up with the final assertion failing.
I’ve tested this example without and with the modification in CI:
(1) src/thread/pthread_create.c line 255 in musl v1.2.3
This was discovered investigating a segfault in the OCaml runtime, where some information is stored in the TSD in all cases, even for the initial thread. Accessing that information after a new thread has been created triggered the segfault.