480032 - "Conditional jump or move depends on uninitialised value(s)" [@ _cairo_restrict_value]

Status: RESOLVED FIXED

(Core :: Graphics, defect)

Description

[Mats Palmgren (inactive)]

Attachment: valgrind 3.4.0 log, with --track-origins=yes

"Conditional jump or move depends on uninitialised value(s)" [@ _cairo_restrict_value]

STEPS TO REPRODUCE
0. build Firefox trunk debug with:
ac_add_options --enable-tests
ac_add_options --enable-optimize="-fno-omit-frame-pointer -fno-asynchronous-unwind-tables -fno-inline -O -g -ggdb -DDEBUG_TRACEMALLOC_FRAMEARENA"
ac_add_options --enable-debug
ac_add_options --enable-jemalloc
ac_add_options --with-valgrind

1. run it under valgrind

ACTUAL RESULT
see attached valgrind log

In layout/generic/nsImageFrame.cpp:
The uninitialized value is stored locally as 'oldColor' and when it's
restored by SetColor() valgrind detects it eventually (see log):

  1082      // if we could not draw the image, then just draw some graffiti
  1083      if (!iconUsed) {
  1084        nscolor oldColor;
  1085        nscoord iconXPos = (vis->mDirection ==   NS_STYLE_DIRECTION_RTL) ?
  1086                           inner.XMost() - size : inner.x;
  1087        nscoord twoPX = nsPresContext::CSSPixelsToAppUnits(2);
  1088        aRenderingContext.DrawRect(iconXPos, inner.y,size,size);
  1089        aRenderingContext.GetColor(oldColor);
  1090        aRenderingContext.SetColor(NS_RGB(0xFF,0,0));
  1091        aRenderingContext.FillEllipse(size/2 + iconXPos, size/2 + inner.y,
  1092                                      size/2 - twoPX, size/2 - twoPX);
  1093        aRenderingContext.SetColor(oldColor);
  1094      }

Comment 1

[Mats Palmgren (inactive)]

Attachment: Patch rev. 1

Comment 2

[Mats Palmgren (inactive)]

http://hg.mozilla.org/mozilla-central/rev/3c8d3bc99c24

-> FIXED

Comment 4

[Robert Sayre]

we're hitting this on the branch. I think we should take it.

Comment 5

[Jeff Muizelaar [:jrmuizel]]

The patch applies cleanly to 1.9.1

Comment 6

[Mats Palmgren (inactive)]

http://hg.mozilla.org/releases/mozilla-1.9.1/rev/855a70083295