Re: gdb bt gives many question marks

[jojelino <jojelino at gmail dot com>]

On 2013-03-14 PM 6:30, Ken Huang wrote:
> 2013/3/14 jojelino <jojelino@gmail.com>:
> > On 2013-03-14 PM 4:37, Ken Huang wrote:
> > > Hi all,
> > >
> > > I have a problem when using gdb to debug my program in cygwin, the 'bt'
> > > command
> > > gives me many '??'.
> > > (gdb) bt full
> > > #0  0x7c92e514 in ntdll!LdrAccessResource () from
> > > /cygdrive/c/WINDOWS/system32/ntdll.dll
> > > No symbol table info available.
> > > #1  0x7c92df5a in ntdll!ZwWaitForSingleObject () from
> > > /cygdrive/c/WINDOWS/system32/ntdll.dll
> > > No symbol table info available.
> > > #2  0x7c8025db in WaitForSingleObjectEx () from
> > > /cygdrive/c/WINDOWS/system32/kernel32.dll
> > > No symbol table info available.
> > > #3  0x00000714 in ?? ()
> > > No symbol table info available.
> > > #4  0x00000000 in ?? ()
> > > No symbol table info available.
> > >
> > > My test program is as follows:
> > > void bar()
> > > {
> > >       abort();
> > > }
> > >
> > > void foo()
> > > {
> > >       bar();
> > > }
> > >
> > > int main()
> > > {
> > >       foo();
> > > }
> > >
> > > So, did I compile wrong, or is there something I didn't set properly?
> > >
> > > Thanks,
> > > Ken
> >
> > There is no way of identifying stdcall or fastcall ABI for return address
> > that are not annotated by DWARF contained in stack frames in current gdb.
> > you'd better give up or come with patches that solved the problem.
> > --
> > Regards.
>
> So you mean gdb can't help to debug buggy code without patches? but as the
> results I googled before, there are people out there use gdb just like in linux.
>
> Do I need to install some external packages?
>
> Regards,
> Ken
Yes. this is problem of gdb and it failed to detect ebp based stack 
frame. if you wanted figuring out whether SIGABRT signal correctly 
points your code that called abort() then your post clearly revealed 
that it didn't work. and i can't say any external package can be used to 
resolve this problem.
--
Regards.


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