segfault in apic_report_irq_delivered when booting tinycore_3.3.iso

it git head (33cf629) sometimes it segfaults in apic_report_irq_delivered() and backtrace is looping in apic_update_irq(#3-#4)

Log:
C:\msys\home\User\qemu\i386-softmmu>gdb --args qemu-system-i386.exe -L ..\pc-bios -cdrom tinycore_3.3.iso
GNU gdb (GDB) 7.3
Copyright (C) 2011 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "mingw32".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from C:\msys\home\User\qemu\i386-softmmu/qemu-system-i386.exe...
done.
(gdb) r
Starting program: C:\msys\home\User\qemu\i386-softmmu/qemu-system-i386.exe -L ..\\pc-bios -cdrom tinycore_3.3.iso
[New Thread 9012.0x2348]
[New Thread 9012.0x2860]
[New Thread 9012.0x2b64]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 9012.0x2b64]
0x0053cde8 in apic_report_irq_delivered (delivered=0)
    at C:/msys/home/User/qemu/hw/apic_common.c:110
110     {
(gdb) bt
#0  0x0053cde8 in apic_report_irq_delivered (delivered=0)
    at C:/msys/home/User/qemu/hw/apic_common.c:110
#1  0x0053b9eb in apic_set_irq (s=0x1d7aff8, vector_num=<optimized out>,
    trigger_mode=0) at C:/msys/home/User/qemu/hw/apic.c:390
#2  0x0053b990 in apic_update_irq (s=0x1d7aff8)
    at C:/msys/home/User/qemu/hw/apic.c:376
#3  apic_update_irq (s=0x1d7aff8) at C:/msys/home/User/qemu/hw/apic.c:367
#4  0x0053b990 in apic_update_irq (s=0x1d7aff8)
    at C:/msys/home/User/qemu/hw/apic.c:376
#5  apic_update_irq (s=0x1d7aff8) at C:/msys/home/User/qemu/hw/apic.c:367
#6  0x0053b990 in apic_update_irq (s=0x1d7aff8)
    at C:/msys/home/User/qemu/hw/apic.c:376
#7  apic_update_irq (s=0x1d7aff8) at C:/msys/home/User/qemu/hw/apic.c:367
...