bug#24585: 25.1; avoid hack in ggtags.el to run compilation-auto-jump timer

[Leo Liu]

On 2016-10-02 16:35 -0400, Stefan Monnier wrote:
> IIUC this patch just changes the ordering for same-time timers.
> Relying on either ordering is itself a hack.  We need a better solution.

If you eval (progn (run-with-timer 0 ...)  ; timer 1
                   (run-with-timer 0 ...)) ; timer 2

you expect timer 1 to be triggered first, no?

> What are those two timers whose relative execution order matters?
> Why do they care in which order they're run?

The first timer is compilation-auto-jump which is installed (by compile)
at the start of compilation.

The second timer is a cleanup timer which is installed (by ggtags) when
compilation finishes and there is 0 or 1 match.

The second timer kills the buffer (among other things) that the first
timer depends on.

Leo