Bug 189215 – [GTK] ASSERT(!m_nicosia.imageBacking) when starting any YouTube video

• Component: WebKitGTK
• Status: RESOLVED FIXED

[Michael Catanzaro]

Try to play any video on youtube.com and you'll immediately hit this assertion in CoordinatedGraphicsLayer's destructor:

ASSERT(!m_nicosia.imageBacking);

I'll attach a full backtrace. Here's a truncated one:

#0  0x00007fdef9e64f43 in WTFCrash ()
    at /home/mcatanzaro/Projects/WebKit/Source/WTF/wtf/Assertions.cpp:267
#1  0x00007fdefbef8193 in WebCore::CoordinatedGraphicsLayer::~CoordinatedGraphicsLayer (
    this=0x7fde7cdc4780, __in_chrg=<optimized out>)
    at /home/mcatanzaro/Projects/WebKit/Source/WebCore/platform/graphics/texmap/coordinated/CoordinatedGraphicsLayer.cpp:141
#2  0x00007fdefbef86cb in WebCore::CoordinatedGraphicsLayer::~CoordinatedGraphicsLayer (
    this=0x7fde7cdc4780, __in_chrg=<optimized out>)
    at /home/mcatanzaro/Projects/WebKit/Source/WebCore/platform/graphics/texmap/coordinated/CoordinatedGraphicsLayer.cpp:135
#3  0x00007fdefd45c23b in std::default_delete<WebCore::GraphicsLayer>::operator() (
    __ptr=<optimized out>, this=0x7fde80d3dbd0)
    at /home/mcatanzaro/Projects/WebKit/Source/WebCore/rendering/RenderLayerBacking.cpp:468
#4  std::unique_ptr<WebCore::GraphicsLayer, std::default_delete<WebCore::GraphicsLayer> >::reset (
    __p=<optimized out>, this=0x7fde80d3dbd0) at /usr/include/c++/8/bits/unique_ptr.h:382
#5  std::unique_ptr<WebCore::GraphicsLayer, std::default_delete<WebCore::GraphicsLayer> >::operator=(decltype(nullptr)) (this=0x7fde80d3dbd0) at /usr/include/c++/8/bits/unique_ptr.h:318
#6  WebCore::RenderLayerBacking::destroyGraphicsLayers (this=this@entry=0x7fde80d3dbb0)
    at /home/mcatanzaro/Projects/WebKit/Source/WebCore/rendering/RenderLayerBacking.cpp:468
#7  0x00007fdefd482834 in WebCore::RenderLayerBacking::~RenderLayerBacking (this=0x7fde80d3dbb0, 
    __in_chrg=<optimized out>)
    at /home/mcatanzaro/Projects/WebKit/Source/WebCore/rendering/RenderLayerBacking.cpp:249
#8  0x00007fdefd482903 in WebCore::RenderLayerBacking::~RenderLayerBacking (this=0x7fde80d3dbb0, 
    __in_chrg=<optimized out>)
    at /home/mcatanzaro/Projects/WebKit/Source/WebCore/rendering/RenderLayerBacking.cpp:238
#9  0x00007fdefd4829c9 in std::default_delete<WebCore::RenderLayerBacking>::operator() (
    __ptr=<optimized out>, this=0x7fde80d57960)
    at /home/mcatanzaro/Projects/WebKit/Source/WebCore/rendering/RenderLayer.cpp:5977
#10 std::unique_ptr<WebCore::RenderLayerBacking, std::default_delete<WebCore::RenderLayerBacking> >::reset (__p=<optimized out>, this=0x7fde80d57960) at /usr/include/c++/8/bits/unique_ptr.h:382

[Michael Catanzaro]

Created attachment 348680 [details]
Full backtrace

[Michael Catanzaro]

BTW, these destructors are quite tricky (bug #180232)

[Zan Dobersek]

Created attachment 348906 [details]
Patch

[Zan Dobersek]

Comment on attachment 348906 [details]
Patch

Clearing flags on attachment: 348906

Committed r235671: <https://trac.webkit.org/changeset/235671>

[Zan Dobersek]

All reviewed patches have been landed.  Closing bug.