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From: "Appelmans, Madeleine" <>
To: "" <>
Subject: [musl] Difference in pthread behavior between glibc and musl
Date: Tue, 11 Jul 2023 19:19:50 +0000	[thread overview]
Message-ID: <> (raw)

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There seems to be a difference in pthread behavior when compiling with glibc and using the musl-gcc wrapper. The attached snippet of code creates a destructor attribute which deletes a pthread key. The code never actually creates the pthread key. This code segfaults when compiled using musl-gcc, and does not segfault when compiled with gcc.

Best guess at what is going on: When creating a pthread key, musl initializes a field called tsd<>. When deleting a key, musl assumes that initialization has been done, and dereferences tsd without checking that it exists: see here<>. This dereference may be the source of the segfault.


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[-- Attachment #2: pthread_test.c --]
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#include <pthread.h>

static pthread_key_t per_thread_key;

static void __attribute__((destructor)) key_cleanup(void)

int main(int argc, char **argv)
    // Do nothing

             reply	other threads:[~2023-07-11 19:24 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-07-11 19:19 Appelmans, Madeleine [this message]
2023-07-11 19:42 ` Markus Wichmann
2023-07-12  2:48 ` Rich Felker
2023-07-13  1:00   ` Gabriel Ravier
2023-07-13  1:50     ` Rich Felker
2023-07-13  2:02       ` Gabriel Ravier
2023-07-13 16:27         ` Markus Wichmann
2023-07-13 18:49           ` Gabriel Ravier

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