739168 - hang in JS parser

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Daniel Glazman (:glazou) (not active in Mozilla any more)]

The attached URL freezes Nightly Gecko/20120325 Firefox/14.0a1
(Built from http://hg.mozilla.org/mozilla-central/rev/20a01901480f)
on both Mac OS X (tested by myself) and Win64 (tested by Neil Rashbrook).

Neil said on IRC it is hanging in the JS parser, hence the bug component
and bug summary chosen.

That's a regression, it works for me on a 20120324 Mac OS X build
built from mozilla-central rev df1f94b2bdee.

Comment 1

[[e-mail]]

It turns out that I had strict JS warnings enabled, and my console had filled with a huge number of copies of the following warning:

JavaScript warning: http://www.google.com/uds/api/elements/1.0/79d660335e8f0082088b4c7944ed5eb3/inputtools.js, line 1: octal literals and octal escape sequences are deprecated

Comment 2

[Boris Zbarsky [:bzbarsky]]

The warning in comment 1 is new, and expected....

The fact that strict warning can cause lots of slowness is known and has existing bugs covering it.

Comment 3

[David Mandelin [:dmandelin]]

Not tracking because it's a long-known bug.

Comment 4

[Dão Gottwald [:dao]]

That doesn't really help. That strict warnings can cause slowness may be a long-known bug, but if a new warning is triggered a lot (and we can't get rid of the overhead) it may mean we have to disable the warning.

Comment 5

[David Mandelin [:dmandelin]]

dcamp, do you remember this stuff about lots of warnings going the console causing slowdowns? bz refers to it above, and ISTR something like that, but I can't actually find the existing bugs.

Comment 6

[Dave Camp (:dcamp)]

I don't know of any. Mihai or Rob, do you guys remember any bugs about console errors causing slowdowns?

Comment 7

[Nicholas Nethercote [inactive]]

Bug 634444 may be relevant if there are long lines involved.

Comment 8

[Rob Campbell [:rc] (:robcee)]

we have this:

https://bugzilla.mozilla.org/show_bug.cgi?id=722685

though not really related to Console Logging itself being slow.

Comment 9

[David Mandelin [:dmandelin]]

I don't think I've seen bug 722685 before but it looks related. I think bug 634444 is the one I remember from a while back.

Comment 10

[Rob Campbell [:rc] (:robcee)]

Bug 634444 looks pretty similar to this bug.

Comment 11

[Dão Gottwald [:dao]]

So this only affects people having a console open?

Comment 12

[Dão Gottwald [:dao]]

Removing my tracking request under the assumption that this doesn't affect ordinary users...

Comment 13

[Nicholas Nethercote [inactive]]

Bug 634444 was fixed a long time ago.  I'm assuming it fixes this problem.  Please reopen if not.