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gdb bt gives many question marks
- From: Ken Huang <csuhgw at gmail dot com>
- To: cygwin at cygwin dot com
- Date: Thu, 14 Mar 2013 15:37:30 +0800
- Subject: gdb bt gives many question marks
- References: <603c2ab2.23bed.13d67af2820.Coremail.hgw00@126.com>
Hi all,
I have a problem when using gdb to debug my program in cygwin, the 'bt' command
gives me many '??'.
So I write a quite easy program named abort.c which just aborts. after
compiled with
"gcc -g abort.c -o abort" and run with " gdb abort", it aborts as
expected. At this time
I type "bt" in gdb to see the backtrace info, but it only gives the following:
(gdb) bt
#0 0x7c92e514 in ntdll!LdrAccessResource () from
/cygdrive/c/WINDOWS/system32/ntdll.dll
#1 0x7c92df5a in ntdll!ZwWaitForSingleObject () from
/cygdrive/c/WINDOWS/system32/ntdll.dll
#2 0x7c8025db in WaitForSingleObjectEx () from
/cygdrive/c/WINDOWS/system32/kernel32.dll
#3 0x00000714 in ?? ()
#4 0x00000000 in ?? ()
(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
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