178045 - floating point error when using gtk2 on startup

Status: RESOLVED FIXED

(Core :: XUL, defect)

Description

[Christopher Blizzard (:blizzard)]

From bug #176842:


------- Additional Comment #11 From Geoff Leach 2002-11-01 21:55 -------

With this patch (from CVS checkout based build) I get

###!!! ASSERTION: Computed Size < 0: 'aReflowState.mComputedWidth >=0 &&
aReflowState.mComputedHeight >= 0', file nsBoxFrame.cpp, line 803
Break: at file nsBoxFrame.cpp, line 803
/home/gl/mozilla/dist/bin/run-mozilla.sh: line 444:  1147 Floating point
exception"$prog" ${1+"$@"}

When I back the patch out  the above does not occur.

.mozconfig
ac_add_options --enable-svg
ac_add_options --enable-crypto
ac_add_options --enable-default-toolkit=gtk2
ac_add_options --disable-toolkit-gtk
ac_add_options --disable-toolkit-qt
ac_add_options --enable-xft
ac_add_options --enable-freetype2
ac_add_options --enable-cpp-rtti
ac_add_options --enable-cpp-exceptions
ac_add_options --enable-extensions
ac_add_options --with-system-jpeg
ac_add_options --with-system-zlib
ac_add_options --with-system-png
ac_add_options --with-system-mng
#ac_add_options --enable-calendar
MOZ_INTERNAL_LIBART_LGPL=1
mk_add_options MOZ_INTERNAL_LIBART_LGPL=1
#MOZ_CALENDAR=1
#mk_add_options MOZ_CALENDAR=1

Comment 1

[Christopher Blizzard (:blizzard)]

OK, then, something is still wrong.

I need some pieces of information:

Are you using Red Hat 8.0?

Are you using a hand built copy of Gtk?

If so, what version?

Can you do an: 'xrdb -q -all' and paste the output here?  (I'm looking
specifically for a line that says something like 'Xft.dpi: 96.0000000')

If you're really adventurous, we can do some debugging.  I suspect that
GetOSDPI() is returning a bogus value - I just want to know what part of it is
doing so.

Comment 2

[Geoff Leach]

Attachment: Output from xrdb -q -all

Output from xrdb -q -all

Comment 3

[Geoff Leach]

Yes, stock "up2date'd" RH 8.0 which has gtk2-2.0.6-8

>xrdb -q -all | grep -i dpi
Xft.dpi:        96

(but not "Xft.dpi: 96.0000000")

Comment 4

[Christopher Blizzard (:blizzard)]

If you're using RH8 with gtk2 you shouldn't even get that far:

  if (spec) {
    g_object_get(G_OBJECT(settings),
                 "gtk-xft-dpi", &dpi,
                 NULL);
  }

  if (dpi)
    return NSToCoordRound(dpi / PANGO_SCALE);


Can you tell me what is being returned there?

Comment 5

[Geoff Leach]

dpi is being set to -1 from the call to g_object_get


In /usr/include/pango-1.0/pango/pango-types.h
#define PANGO_SCALE 1024

return value is 0 due to integer division of
dpi / PANGO_SCALE

Comment 6

[Geoff Leach]

Just tried using Gnome rather than KDE. It works.

dpi:98304
PANGO_SCALE: 1024
return value: 96

Comment 7

[Christopher Blizzard (:blizzard)]

Wait, are you saying that if you log in using a KDE-based desktop that that call
is returning a -1?

wtf?

Comment 8

[Christopher Blizzard (:blizzard)]

Attachment: patch

Owen says that (surprise!) the default is -1 if the value is unset.  Easy to
detect.

Comment 9

[Christopher Blizzard (:blizzard)]

Attachment: patch

also, the scale factor is 1024, unrelated to PANGO_SCALE

Comment 10

[Christopher Blizzard (:blizzard)]

Attachment: patch

Add a .0 to promote the divisor to a float.

Comment 11

[Christopher Blizzard (:blizzard)]

Comment on attachment 105114 [details] [diff] [review]
patch

from irc:

r=otaylor

Comment 12

[Scott Collins]

Comment on attachment 105114 [details] [diff] [review]
patch

sr=scc

Comment 13

[Randell Jesup [:jesup] (needinfo me)]

Comment on attachment 105114 [details] [diff] [review]
patch

a=[e-mail] for trunk; please consider for 1.0 branch too (this appears
to be general gtk code; I'm not sure if it's relevant to 1.0)

Comment 14

[Christopher Blizzard (:blizzard)]

Checked in.

Just FYI, this code isn't on the 1.0 branch at all.