gdb backtrace for g++ programs showing ?? symbol

[naam nahin]

Hi,

I am trying to debug a C++ program on Linux. g++ version is 4.1.3.

While debugging the program under gdb, I get a SIGABRT with the following backtrace:

#0  0xffffe410 in __kernel_vsyscall ()
#1  0xb7ce7875 in raise () from /lib/tls/i686/cmov/libc.so.6
#2  0xb7ce9201 in abort () from /lib/tls/i686/cmov/libc.so.6
#3  0xb7ef36e0 in __gnu_cxx::__verbose_terminate_handler () from /usr/lib/libstdc++.so.6
#4  0xb7ef0f65 in ?? () from /usr/lib/libstdc++.so.6
#5  0xb7ef0fa2 in std::terminate () from /usr/lib/libstdc++.so.6
#6  0xb7ef10ca in __cxa_throw () from /usr/lib/libstdc++.so.6
#7  0x08048a5e in foo ()
#8  0x08048ac6 in main ()

It is expected because I am not catching the exception I am throwing.

However, I don't know why I see "??" as the function symbol in frame 4. Why can't gdb show me the function name for that function?

Thanks in advance,
Yaad Nahin