From: Stefan Weil <weil@mail.berlios.de>
To: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Re: SIGSEGV on Windows with KQEMU enabled
Date: Sun, 15 Mar 2009 17:16:50 +0100 [thread overview]
Message-ID: <49BD29F2.9000400@mail.berlios.de> (raw)
In-Reply-To: <200903150042.58341.paul@codesourcery.com>
Paul Brook schrieb:
>>> But really funny think is the change that triggers the bug is precisely
>>> this: -Monitor *cur_mon;
>>> +Monitor *cur_mon = NULL;
>>>
>>> Obviously, kqemu is happier having garbage in the cur_mon than NULL
>>>
>> I rather expect that to _hide_ the bug. The "garbage" might be a
>> left-over from the heap.
>>
>
> This change does precisely nothing. In C all global and static variables are
> implicitly zero initialized.
>
> Paul
>
>
>
This change changes the location of variable cur_mon from BSS to DATA
segment.
For buggy code, such changes surely can have an effect. Maybe some other
variable in data which is located before cur_mon destroys cur_mon.
Running in gdb with a hardware watchpoint on any change of cur_mon might
help
to see if cur_mon is overwritten.
Stefan
next prev parent reply other threads:[~2009-03-15 16:17 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-07 0:39 [Qemu-devel] SIGSEGV on Windows with KQEMU enabled Consul
2009-03-07 2:51 ` Anthony Liguori
2009-03-13 1:28 ` [Qemu-devel] " Consul
2009-03-13 10:37 ` Johannes Schindelin
2009-03-13 17:33 ` Consul
2009-03-14 12:16 ` Johannes Schindelin
2009-03-14 12:36 ` Andreas Färber
2009-03-15 0:42 ` Paul Brook
2009-03-15 16:16 ` Stefan Weil [this message]
2009-03-15 16:39 ` Avi Kivity
2009-03-16 10:22 ` Johannes Schindelin
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