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qmlscene segfaults with a lot of objects



  • Hi all,

    I'm working on an animated desktop for KDE. I'm using qmlscene to help me. My projects uses a lot of rectangles as "pixels" since it's a bit of pixel art. I've gotten up to about 2500 rectangles. At some point I added another batch and when I ran qmlscene ./main.qml it segfaults. When I added a bunch more it reported:

    realloc(): invalid next size
    Aborted (core dumped)
    

    so I started adding one rectangle at a time and it would load but when I get to the final rectangle it spits out:

    qmlscene: malloc.c:2401: sysmalloc: Assertion `(old_top == initial_top (av) && old_size == 0) || ((unsigned long) (old_size) >= MINSIZE && prev_inuse (old_top) && ((unsigned long) old_end & (pagesize - 1)) == 0)' failed.
    Aborted (core dumped)
    

    only on that final object. After that it will just report the segmentation fault. It is not one specific rectangle either. It's the number that seems to matter.
    Anyone run into this? Have I hit past the "MAX RECTANGLE or OBJECT" parameter perhaps? Is there a limit? I don't think I'm using a crazy amount of memory either...

    Thanks!

    Edit: I'm on KUbuntu 18.04 which I believe is using QT version

    I have an example of the code. I don't have enough rep to post it here but I could attach it to the bug post I made. Is there a way around this rectangle limit though or to allocate more space somehow?
    https://bugreports.qt.io/browse/QTBUG-71195


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