On Sun, Jun 05, 2005 at 09:42:12AM +0200, Matijs van Zuijlen wrote: > Package: gdb > Version: 6.3-5 > Severity: normal > > I'm not sure what is wrong, but often when I try to debug a program that > uses threads, I cannot get a proper backtrace. Instead, I get something > like this (the example is from gst-compprep-0.8): > > Program received signal SIGILL, Illegal instruction. > 0x0f08de24 in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > (gdb) where > #0 0x0f08de24 in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #1 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #2 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #3 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #4 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #5 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #6 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #7 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #8 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #9 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #10 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #11 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > #12 0x0f08dd4c in mpeg2_detect_accel () from /usr/lib/libmpeg2.so.0 > Previous frame inner to this frame (corrupt stack?) > (gdb)
This will have nothing to do with threads. Probably that library is compiled with -fomit-frame-pointer and does not include debugging information; that means that GDB simply can't figure out the stack frame. The only way to fix this is to build a debug version, in general. Looking at the disassembly for the function it isn't reasonable to expect GDB to understand what's going on (esp. the use of pushf/popf). -- Daniel Jacobowitz CodeSourcery, LLC -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
