bug#57684: locked narrowing breaks existing code without an apparent way to repair

[Paul Pogonyshev]

Well, probably not it then.

> Files with very long lines are typically machine-generated

Typically, but not always. The Logview hangs for me likely were because the logs I worked with contained long command lines for Java process starting (when you use a huge application with over 100 library JARs, classpath specification can get _really_ long). Actually, in a sense, those are machine-generated too, but the files are meant for human consumption, not e.g. as generated sources that are fed to a compiler.

Anyway, I really hope something is done about this soon so that I don't have to switch between Emacs 29 and 28 all the time.

Paul

On Tue, 13 Sept 2022 at 23:06, Gregory Heytings <gregory@heytings.org> wrote:

>
> By the way, today Emacs 29 hung in Magit blaming for me, with C-g doing
> nothing. Grepping Magit sources suggest it uses the "save-restriction -
> temporarily widen" more than ten times in various places, 3 of them when
> blaming. Cannot say for sure that was it, but all the outer symptoms are
> identical with the hangs in Logview. I really think there must be a way
> to "widen no matter which locks are installed" - a lot of code seems to
> depend on that.
>

Yes, we know that, and as I said earlier it will be possible to unlock a
locked narrowing.  That being said, your description is too vague to draw
a conclusion, but given that you tell that Emacs hung in Magit, I'm not
quite sure it's locked narrowing that is the culprit.  Locked narrowing is
currently used only in buffers with very long lines, and only when those
buffers are on display.  Files with very long lines are typically
machine-generated, and not under version control.