David Daney writes: > Andrew Haley wrote: > > PRC writes: > > > > > Gcc saves the frame pointer to fp(s8) register at the beginning of > > > each function if compiling source with -O0. But it won't do so if > > > compiling source with -O2. Without frame pointers, can I trace back > > > call stacks in current function context? Or is there any option > > > which forces gcc to save frame pointers for MIPS arch? > > > > You need to use the unwinder. > > > For that to work, you must compile all the code with -fexceptions. Or just -funwind-tables. Yes, I should have mentioned that. It's kinda lame that we break the old way of doing backtraces but don't compile the minimum unwinder data by default. Sigh. > You could also try compiling all the code with -fno-omit-framepointer > and writing your own unwinder. I posted such an unwinder to > java-patches@xxxxxxxxxxx several years ago. Later versions of GCC are > starting to do optimizations in the function prolog that make unwinding > without the unwinder meta-data very difficult. Right, which as far as I can see is the OP's problem. Andrew. -- Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, UK Registered in England and Wales No. 3798903
