[Libunwind-devel] Backtrace on ARM

[Richard Titmuss]

Hi,

I am trying to output a backtrace in a signal handler (for sigquit and 
sigsegv) in an ARM application on an embedded platform. It appears that 
two different approaches can be used, backtrace in glibc and using 
libunwind. In fact the Ltest-bt included in libunwind looks like a 
perfect example of what I am trying to do. However it does not seem to 
be working for me, it outputs:

   # ./Ltest-bt v
   Normal backtrace:
           explicit backtrace:
   0000000000008a88 <do_backtrace+0x38>              (sp=00000000be849620)
           proc=12-4001e000
           handler=400fb3e0 lsda=4001fad0 gp=1

           via backtrace():
   ...

The backtrace from all three tests are identical, just showing the 
do_backtrace function and not unwinding the stack. Also the glibc 
backtrace is not returning any results. I have tried experimenting with 
different compiler options, and a couple of different toolchains. My 
latest tests are using the CodeSourcery lite 2008q3-72 toolchain.

Is there something obvious that I am missing to get this to work?

Thanks,
Richard