Re: emacs hangs in jit-lock

[Chong Yidong <cyd@stupidchicken.com>]

Sam Steingold <sds@gnu.org> writes:

> "line-end-position" (0x29e02)
> "back-to-indentation" (0x2e0)
> "c-beginning-of-macro" (0x27bda8)
> "byte-code" (0xa5c7eab)
> "c-parse-state" (0x27bda8)
> "c-font-lock-complex-decl-prepare" (0x27d0b8)
> "font-lock-fontify-keywords-region" (0x27bda8)
> "font-lock-default-fontify-region" (0x27bda8)
> "font-lock-fontify-region" (0x27bda8)
> "run-hook-with-args" (0x840af31)
> "byte-code" (0x822f25b)
> "jit-lock-fontify-now" (0x27bed8)
> "jit-lock-stealth-fontify" (0x83178f9)
>
> the problem is that this unresponsiveness can last for MINUTES (I am not
> making this up!) and the periods of responsiveness can last for mere
> SECONDS.
>
> Even if it should, any input from me should immediately interrupt it -
> and I see my C-g "delayed" for minutes.

Since jit-lock-stealth fontify is run as an idle timer, any input
*does* interrupt it.  The only way this could fail is if the
c-font-lock functions interfere with this---either by somehow
resetting the idleness state, or (more likely) taking a very long
time.

If you provided a simple test case, I or someone else could take a
look at this problem.