From: Mark Geisert <mark@maxrnd.com>
To: cygwin-developers@cygwin.com
Subject: Re: malloc crash
Date: Mon, 25 Oct 2021 16:36:50 -0700 [thread overview]
Message-ID: <2819d0db-3c5c-2d31-2b21-91efafb7f8f4@maxrnd.com> (raw)
In-Reply-To: <4b322eb0-4941-6b8f-6f46-aa76caf5a66f@cornell.edu>
Ken Brown wrote:
> On 10/25/2021 5:29 PM, Mark Geisert wrote:
>> Corinna Vinschen wrote:
>>> On Oct 25 08:35, Ken Brown wrote:
>>>> On 10/25/2021 4:59 AM, Corinna Vinschen wrote:
>>>>> Has the thread already been started at this point?
>>>>
>>>> Yes, here's the backtrace of that thread:
>>>>
>>>> Thread 5 (Thread 9692.0x7c4c):
>>>> #0 0x00000001801934f9 in sys_alloc (m=0x18036f860 <_gm_>, nb=1040) at
>>>> ../../../../temp/winsup/cygwin/malloc.cc:4232
>>>> #1 0x0000000180196b96 in dlmalloc (bytes=1024) at
>>>> ../../../../temp/winsup/cygwin/malloc.cc:4669
>>>> #2 0x00000001801993e1 in dlrealloc (oldmem=0x0, bytes=1024) at
>>>> ../../../../temp/winsup/cygwin/malloc.cc:5187
>>>> #3 0x00000001800e8eed in realloc (p=0x0, size=1024) at
>>>> ../../../../temp/winsup/cygwin/malloc_wrapper.cc:73
>>>
>>> Er... huh? So both threads are in a malloc function? This shouldn't
>>> have happened, given the clunky muto guarding malloc calls. This is
>>> really strange. Why's the muto not working here?
>>
>> Is it possible both threads have executed malloc_init()?
>> If so, the second one would reinit the muto.
>
> Or does the fifo_reader thread call a malloc function before the main thread has
> called malloc_init()? This would presumably cause __malloc_lock() to fail, but
> there's no error check.
If there's a global constructor involved, that is known to happen. Constructors
are run from dll_crt0_0(), before malloc_init() is called from dll_crt0_1(). See
dcrt0.cc for the details.
..mark
next prev parent reply other threads:[~2021-10-25 23:36 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-24 21:46 Ken Brown
2021-10-25 8:56 ` Takashi Yano
2021-10-25 13:37 ` Ken Brown
2021-10-25 8:59 ` Corinna Vinschen
2021-10-25 12:35 ` Ken Brown
2021-10-25 15:39 ` Corinna Vinschen
2021-10-25 21:29 ` Mark Geisert
2021-10-25 22:02 ` Ken Brown
2021-10-25 23:36 ` Mark Geisert [this message]
2021-10-26 0:18 ` Takashi Yano
2021-10-26 0:54 ` Mark Geisert
2021-10-26 8:30 ` Mark Geisert
2021-10-26 8:52 ` Takashi Yano
2021-10-26 8:59 ` Mark Geisert
2021-10-26 9:26 ` Takashi Yano
2021-10-26 9:31 ` Corinna Vinschen
2021-10-26 9:28 ` Corinna Vinschen
2021-10-26 9:27 ` Corinna Vinschen
2021-10-26 9:24 ` Corinna Vinschen
2021-10-26 14:32 ` Ken Brown
2021-10-26 16:03 ` Corinna Vinschen
2021-10-26 16:36 ` Ken Brown
2021-10-26 16:49 ` Corinna Vinschen
2021-10-26 17:10 ` Ken Brown
2021-10-27 0:44 ` Takashi Yano
2021-10-27 9:01 ` Corinna Vinschen
2021-10-26 16:44 ` Takashi Yano
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