foobar.diff

diff --git a/scene_opengl.cpp b/scene_opengl.cpp
index 8b3be71..f22e2ad 100644
--- a/scene_opengl.cpp
+++ b/scene_opengl.cpp
@@ -464,6 +464,39 @@ static void scheduleVboReInit()
     timer->start(250);
 }
 
+static void APIENTRY someCallback(GLenum source, GLenum type, GLuint id,
+                       GLenum severity, GLsizei length,
+                       const GLchar *message,
+                       const GLvoid *userParam) {
+        Q_UNUSED(source)
+        Q_UNUSED(severity)
+        Q_UNUSED(userParam)
+        while (message[length] == '\n' || message[length] == '\r')
+            --length;
+
+        switch (type) {
+        case GL_DEBUG_TYPE_ERROR:
+        case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR:
+            qCWarning(KWIN_CORE, "%#x: %.*s", id, length, message);
+            break;
+
+        case GL_DEBUG_TYPE_OTHER:
+            // at least the nvidia driver seems prone to end up with invalid VBOs after
+            // transferring them between system heap and VRAM
+            // so we re-init them whenever this happens (typically when switching VT, resuming
+            // from STR and XRandR events - #344326
+            if (strstr(message, "Buffer detailed info:") && strstr(message, "has been updated"))
+                scheduleVboReInit();
+            // fall through! for general message printing
+        case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR:
 
+static void APIENTRY someCallback(GLenum source, GLenum type, GLuint id,
+                       GLenum severity, GLsizei length,
+                       const GLchar *message,
+                       const GLvoid *userParam) {
+        Q_UNUSED(source)
+        Q_UNUSED(severity)
+        Q_UNUSED(userParam)
+        while (message[length] == '\n' || message[length] == '\r')
+            --length;
+
+        switch (type) {
+        case GL_DEBUG_TYPE_ERROR:
+        case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR:
+            qCWarning(KWIN_CORE, "%#x: %.*s", id, length, message);
+            break;
+
+        case GL_DEBUG_TYPE_OTHER:
+            // at least the nvidia driver seems prone to end up with invalid VBOs after
+            // transferring them between system heap and VRAM
+            // so we re-init them whenever this happens (typically when switching VT, resuming
+            // from STR and XRandR events - #344326
+            if (strstr(message, "Buffer detailed info:") && strstr(message, "has been updated"))
+                scheduleVboReInit();
+            // fall through! for general message printing
+        case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR:
+        case GL_DEBUG_TYPE_PORTABILITY:
+        case GL_DEBUG_TYPE_PERFORMANCE:
+        default:
+            qCDebug(KWIN_CORE, "%#x: %.*s", id, length, message);
+            break;
+        }
+}
+
 void SceneOpenGL::initDebugOutput()
 {
     const bool have_KHR_debug = hasGLExtension(QByteArrayLiteral("GL_KHR_debug"));
@@ -511,7 +544,7 @@ void SceneOpenGL::initDebugOutput()
         return;
     }
 
-    glDebugMessageCallback(callback, nullptr);
+    glDebugMessageCallback(someCallback, nullptr);
 
     // This state exists only in GL_KHR_debug
     if (have_KHR_debug)

gistfile1.txt

Breakpoint 1, KWin::SceneOpenGL::initDebugOutput (this=0x132480) at /home/live/kwin/scene_opengl.cpp:547
547         glDebugMessageCallback(someCallback, nullptr);
(gdb) s

Program received signal SIGSEGV, Segmentation fault.
0x00000000 in ?? ()
(gdb) where
#0  0x00000000 in ?? ()
#1  0xb6eb7810 in KWin::SceneOpenGL::initDebugOutput (this=0x132480) at /home/live/kwin/scene_opengl.cpp:547
#2  0xb6eb70dc in KWin::SceneOpenGL::SceneOpenGL (this=0x132480, backend=0x152820, parent=0xb3c70) at /home/live/kwin/scene_opengl.cpp:412
#3  0xb6eba02c in KWin::SceneOpenGL2::SceneOpenGL2 (this=0x132480, backend=0x152820, parent=0xb3c70) at /home/live/kwin/scene_opengl.cpp:1024
#4  0xb6eb7982 in KWin::SceneOpenGL::createScene (parent=0xb3c70) at /home/live/kwin/scene_opengl.cpp:597
#5  0xb6e9f720 in KWin::Compositor::slotCompositingOptionsInitialized (this=0xb3c70) at /home/live/kwin/composite.cpp:219
#6  0xb6e9f43a in KWin::Compositor::setup (this=0xb3c70) at /home/live/kwin/composite.cpp:177
#7  0xb6f54068 in KWin::Compositor::qt_static_metacall (_o=0xb3c70, _c=QMetaObject::InvokeMetaMethod, _id=14, _a=0xb1b68) at /home/live/kwin/build/moc_composite.cpp:261
#8  0xb53b94f8 in QObject::event(QEvent*) () from /usr/lib/arm-linux-gnueabihf/libQt5Core.so.5
#9  0xb593a9e4 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/arm-linux-gnueabihf/libQt5Widgets.so.5
#10 0xb593e8bc in QApplication::notify(QObject*, QEvent*) () from /usr/lib/arm-linux-gnueabihf/libQt5Widgets.so.5
#11 0x0002cfb8 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)