[Webkit-unassigned] [Bug 13147] New: RenderTableCell::sortBorderStyles does not meet qsort's contract

[bugzilla-daemon at webkit.org]

http://bugs.webkit.org/show_bug.cgi?id=13147

           Summary: RenderTableCell::sortBorderStyles does not meet qsort's
                    contract
           Product: WebKit
           Version: 522+ (nightly)
          Platform: All
        OS/Version: Mac OS X 10.4
            Status: UNCONFIRMED
          Severity: Normal
          Priority: P2
         Component: CSS
        AssignedTo: webkit-unassigned at lists.webkit.org
        ReportedBy: phanna at email.unc.edu


When sorting CollapsedBorderStyles with qsort, the comparator function
(compareBorderStylesForQSort) does not honor the requirement that cmp(a, b) ==
cmp(b, a). This does not appear for the qsort implementation on the Mac but if
you use a bubblesort instead of qsort, the problem appears.

The issue is that two borders differ only by color and so compareBorders()
returns the first parameter each time it is called. This means that calling
compareBorders(a, b) != compareBorders(b, a) and thus
compareBorderStylesForQSort(a, b) != compareBorderStylesForQSort(b, a) and so
an infinite loop can occur because the sorting algorithm will constantly swap
the two values.


-- 
Configure bugmail: http://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug, or are watching the assignee.