bug#15045: Point jumps inappropriately around time of Semantic lexing

[Eli Zaretskii]

> Date: Thu, 8 Aug 2013 16:03:30 -0400
> From: Barry OReilly <gundaetiapo@gmail.com>
> Cc: Stefan Monnier <monnier@iro.umontreal.ca>, 15045@debbugs.gnu.org, 
>       "Eric M. Ludlam" <eric@siege-engine.com>, Eli Zaretskii <eliz@gnu.org>
> 
> If arbitrary timers can execute during the lexer's call to
> accept-process-output or input-pending-p, then doesn't that mean
> jit-lock-deferred-fontify can run too?

Not normally, because jit-lock-deferred-fontify runs off an idle
timer, and Emacs is not idle in the situation you describe.