Some more info about that infinite loop in cygwin1.dll .
This is indeed inside the cygheap_fixup_in_child function of cygwin1.dll .
Inside this function, there is a loop that is:
for (_cmalloc_entry *rvc = cygheap->chain; rvc; rvc = rvc->prev) {
...
}
In the case of my sh.exe process , this loop never ends because it is stuck
with an "rvc" pointer that is such that "rvc->prev == rvc"
I'm not sure what to look at, is there a chance that this is an "easy" bug to
fix ?
--
Julien
> Hi,
>
> I have some quite large and long build scripts running on cygwin, on
> some occasions (really rare), the build script just stops progressing.
> Looking at the processes with "process explorer", I always notice that
> one sh.exe is stuck, taking 100% of a core. The stack for that hang
> process is:
>
> cygwin1.dll!setprogname+0x10b3
> cygwin1.dll!__rcmd_errstr+0x788c0
> cygwin1.dll!setprogname+0x10b3
> cygwin1.dll!__main+0x141a
> cygwin1.dll!dll_en...@12+0x2d9
> ntdll.dll!RtlDestroyQueryDebugBuffer+0xff
> ntdll.dll!LdrFindResourceDirectory_U+0x9cc
> ntdll.dll!RtlGetNtVersionNumbers+0x103
> ntdll.dll!LdrInitShimEngineDynamic+0x13f
> ntdll.dll!LdrInitializeThunk+0x10
>
> (I can't attach gdb to it so this is the stack provided by process
> explorer).
>
> If I attach the windbg debugger, I can get the assembly portion the
> loop that executes forever:
>
> 61002900 8b03 mov eax,dword ptr [ebx]
> ds:002b:6127b1ec=00000000
> 61002902 85c0 test eax,eax
> 61002904 741a je cygwin1!setprogname+0x10b0 (61002920)
> 61002906 833b1f cmp dword ptr [ebx],1Fh
> 61002909 7715 ja cygwin1!setprogname+0x10b0 (61002920)
> 6100290b 8b4308 mov eax,dword ptr [ebx+8]
> 6100290e 8d5308 lea edx,[ebx+8]
> 61002911 83f809 cmp eax,9
> 61002914 7e0a jle cygwin1!setprogname+0x10b0 (61002920)
> 61002916 83f863 cmp eax,63h
> 61002919 7f15 jg cygwin1!setprogname+0x10c0 (61002930)
> 6100291b 83c064 add eax,64h
> 6100291e 8902 mov dword ptr [edx],eax
> 61002920 8b5b04 mov ebx,dword ptr [ebx+4]
> 61002923 85db test ebx,ebx
> 61002925 75d9 jne cygwin1!setprogname+0x1090 (61002900)
> 61002927 83c418 add esp,18h
> 6100292a 5b pop ebx
> 6100292b c20400 ret 4
--
Problem reports: http://cygwin.com/problems.html
FAQ: http://cygwin.com/faq/
Documentation: http://cygwin.com/docs.html
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
