On Sun, Jun 04, 2006 at 10:29:14AM -0700, Mark Mitchell wrote: > Daniel Jacobowitz wrote: > > On Sun, Jun 04, 2006 at 09:54:25AM -0700, Mark Mitchell wrote: > >> Richard E. asked what possible uses this function might have. > >> Obviously, GLIBC's backtrace() function is one, though I guess that's a > >> weak example, in that we all agree one should really be using unwind > >> information. > > > > Which there is no plausible way to do for the ARM EABI, due to ARM's > > other choices. > > If one compiled everything with -fexceptions, could you then use the ARM > ABI EH unwind stuff? Or, is there just no way to do this in the ARM EABI?
The DWARF unwinding tables are descriptive; you can interpret them however necessary, for unwinding or for backtraces. But the ARM unwinding tables are more opaque. You have to call the personality routines in order to do anything. I don't believe there's a way to get runtime backtraces from them, reliably. It might be possible to implement _Unwind_Backtrace, but it also might require additional changes similar to those we needed for forced unwind. -- Daniel Jacobowitz CodeSourcery
