gcc - Call stack backtrace in C

Question

I am trying to get call stack backtrace at my assert/exception handler. Can't include "execinfo.h" therefore can't use int backtrace(void **buffer, int size);. Also, tried to use __builtin_return_address() but acording to :http://codingrelic.geekhold.com/2009/05/pre-mortem-backtracing.html

... on some architectures, including my beloved MIPS, only __builtin_return_address(0) works.MIPS has no frame pointer, making it difficult to walk back up the stack. Frame 0 can use the return address register directly.

How can I reproduce full call stack backtrace?

Answer 1

I have successfully used the method described here, to get a call trace from stack on MIPS32.

You can then print out the call stack:

void *retaddrs[16];
int n, i;

n = get_call_stack_no_fp (retaddrs, 16);

printf ("CALL STACK: ");
for (i = 0; i < n; i++) {
    printf ("0x%08X ", (uintptr_t)retaddrs[i]);
}
printf ("
");

... and if you have the ELF file, then use the addr2line to convert the return addresses to function names:

addr2line -a -f -p -e xxxxxxx.elf addr addr ...

There are of course many gotchas, when using a method like this, including interrupts and exception handlers or results of code optimization. But nevertheless, it might be helpful sometimes.