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Subject: Re: [Qemu-devel] Re: SIGSEGV on Windows with KQEMU enabled
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To: qemu-devel@nongnu.org

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