Uploaded image for project: 'Qt'
  1. Qt
  2. QTBUG-87189

Segfault in GridLayoutEngine in QT 5.15.1

    XMLWordPrintable

    Details

    • Type: Bug
    • Status: Reported
    • Priority: P1: Critical
    • Resolution: Unresolved
    • Affects Version/s: 5.15.1
    • Fix Version/s: None
    • Component/s: Widgets: Layout
    • Labels:
      None
    • Environment:
    • Platform/s:
      Linux/X11

      Description

      After upgrading to QT 5.15.1, the plasma-pstate widget used in KDE has started crashing on startup. Below is a relevant dump of the stacktrace that caused plasmashell to crash

       

      systemd-coredump	Process 1765 (plasmashell) of user 1000 dumped core.
      Stack trace of thread 1765:
      #0  0x00007fcb6ceef758 n/a (libQt5Gui.so.5 + 0x49d758)
      #1  0x00007fcb6cef30ce _ZNK17QGridLayoutEngine22ensureColumnAndRowDataEP18QGridLayoutRowDataP14QGridLayoutBoxPKdS5_N2Qt11OrientationEPK24QAbstractLayoutStyleInfo (libQt5Gui.so.5 + 0x4a10ce)
      #2  0x00007fcb6cef34d6 _ZNK17QGridLayoutEngine8sizeHintEN2Qt8SizeHintERK6QSizeFPK24QAbstractLayoutStyleInfo (libQt5Gui.so.5 + 0x4a14d6)
      ...

      Here is the line that is now causing the segfault https://github.com/jsalatas/plasma-pstate/blob/679c14321c1496bf12ca0487c2a520f3361cc98a/gr.ictpro.jsalatas.plasma.pstate/contents/ui/ComboBox.qml#L84

       

      If you comment it out then it stops the crash (however it may cause other issues). On immediate glance of the code there doesn't seem to be anything wrong however it would be great to verify if this was either a regression in Qt or that code was relying on undefined/unspecified behavior.

      There are 2 tickets in plasma-pstate related to this issue

      Noe that if you downgrade to QT 5.15.0 the crash no longer happens.

        Attachments

        No reviews matched the request. Check your Options in the drop-down menu of this sections header.

          Activity

            People

            Assignee:
            qt.team.quick.subscriptions Qt Quick and Widgets Team
            Reporter:
            mdedetrich Matthew de Detrich
            Votes:
            1 Vote for this issue
            Watchers:
            4 Start watching this issue

              Dates

              Created:
              Updated:

                Gerrit Reviews

                There are no open Gerrit changes