Reva includes a debugger, which can be accessed in two ways:

1. From the command-line, add "-d": reva -d
2. Within Reva, type needs debugger

Once active, the debugger will trigger whenever an exception occurs. For example:

ok> 0 !
EDI      ESI      EBX      EDX      ECX      EAX      EBP      ESP      EIP
08049914 0806DA3C 00000000 0806DA94 00000000 00000000 00000001 BF81E274 0806DAA1
Exception SIGSEGV in: !
==> 08049E19 interp
==> 0804A4BA catch
0806DAA1  89 18                       mov [eax],ebx
0806DAA3  AD                          lodsd
0806DAA4  AD                          lodsd
0806DAA5  C3                          ret

Notice the register dump, and the reasonable attempt at back-trace. Because of optimizations, Reva cannot always give the correct back-trace.

The disassembly will proceed until a 'ret' or similar instruction has been reached. To continue the disassembly, type see without arguments and press ENTER.