> That's because target exec does not support reverse,
> but target record does. Reverse is also potentially
> supported under target remote, depending on what remote
> target you're connected to.
>
> > In the "Reverse Execution" node of the GDB manual it talks about
> > "a target environment that supports reverse execution" but doesn't clarify
> > what those targets are. The node "Process Record and Replay" comes next
> > in the manual but these two seem to be inimately related.
>
> Process record (target record) is one of a small number of
> targets that currently support reverse debugging. The others,
> so far, are all remote targets (eg. SID from Red Hat, and
> Simics from Virtutech).
>...
Thanks for these answers, I find them more lucid than the manual. If I try
to reverse a remote target using gdbserver (actually on host/local machine -
x86_64 this time), I'm not told that the target doesn't support this command
but reverse-next works just like next until I hit a function:
(gdb) reverse-next
Program received signal SIGTRAP, Trace/breakpoint trap.
0x0000000000400521 in printf@plt ()
Current language: auto; currently asm
(gdb)