3 files changed, 55 insertions, 5 deletions

diff --git a/src/gui/opengl/qopengldebug.cpp b/src/gui/opengl/qopengldebug.cpp
index 24aa6094dd..f6c3af37dd 100644
--- a/src/gui/opengl/qopengldebug.cpp
+++ b/src/gui/opengl/qopengldebug.cpp
@@ -42,6 +42,7 @@
 #include <QtCore/qvarlengtharray.h>
 #include <QtGui/qopengl.h>
 #include <QtGui/qopenglfunctions.h>
+#include <QtGui/qoffscreensurface.h>
 
 #include "qopengldebug.h"
 
@@ -1287,8 +1288,41 @@ void QOpenGLDebugLoggerPrivate::controlDebugMessages(QOpenGLDebugMessage::Source
 */
 void QOpenGLDebugLoggerPrivate::_q_contextAboutToBeDestroyed()
 {
+    Q_ASSERT(context);
+
+    // Re-make our context current somehow, otherwise stopLogging will fail.
+
+    // Save the current context and its surface in case we need to set them back
+    QOpenGLContext *currentContext = QOpenGLContext::currentContext();
+    QSurface *currentSurface = 0;
+
+    QScopedPointer<QOffscreenSurface> offscreenSurface;
+
+    if (context != currentContext) {
+        // Make our old context current on a temporary surface
+        if (currentContext)
+            currentSurface = currentContext->surface();
+
+        offscreenSurface.reset(new QOffscreenSurface);
+        offscreenSurface->setFormat(context->format());
+        offscreenSurface->create();
+        if (!context->makeCurrent(offscreenSurface.data()))
+            qWarning("QOpenGLDebugLoggerPrivate::_q_contextAboutToBeDestroyed(): could not make the owning GL context current for cleanup");
+    }
+
     Q_Q(QOpenGLDebugLogger);
     q->stopLogging();
+
+    if (offscreenSurface) {
+        // We did change the current context: set it back
+        if (currentContext)
+            currentContext->makeCurrent(currentSurface);
+        else
+            context->doneCurrent();
+    }
+
+    QObject::disconnect(context, SIGNAL(aboutToBeDestroyed()), q, SLOT(_q_contextAboutToBeDestroyed()));
+    context = 0;
     initialized = false;
 }
 
@@ -1494,6 +1528,12 @@ void QOpenGLDebugLogger::stopLogging()
     if (!d->isLogging)
         return;
 
+    QOpenGLContext *currentContext = QOpenGLContext::currentContext();
+    if (!currentContext || currentContext != d->context) {
+        qWarning("QOpenGLDebugLogger::stopLogging(): attempting to stop logging with the wrong OpenGL context current");
+        return;
+    }
+
     d->isLogging = false;
 
     d->glDebugMessageCallback(d->oldDebugCallbackFunction, d->oldDebugCallbackParameter);
diff --git a/src/gui/opengl/qopengltexturehelper_p.h b/src/gui/opengl/qopengltexturehelper_p.h
index 77049dced3..00f6f9e5aa 100644
--- a/src/gui/opengl/qopengltexturehelper_p.h
+++ b/src/gui/opengl/qopengltexturehelper_p.h
@@ -76,6 +76,14 @@ QT_BEGIN_NAMESPACE
 #define GL_TEXTURE_COMPARE_FUNC 0x884D
 #endif
 
+// use GL_APICALL only on Android + __clang__
+#if !defined(Q_OS_ANDROID) || !defined(__clang__)
+# undef GL_APICALL
+# define GL_APICALL
+#elif !defined(GL_APICALL)
+# define GL_APICALL
+#endif
+
 class QOpenGLContext;
 
 class QOpenGLTextureHelper
@@ -754,15 +762,15 @@ private:
     // OpenGL 1.3
     void (QOPENGLF_APIENTRYP GetCompressedTexImage)(GLenum target, GLint level, GLvoid *img);
     void (QOPENGLF_APIENTRYP CompressedTexSubImage1D)(GLenum target, GLint level, GLint xoffset, GLsizei width, GLenum format, GLsizei imageSize, const GLvoid *data);
-    void (QOPENGLF_APIENTRYP CompressedTexSubImage2D)(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLsizei imageSize, const GLvoid *data);
+    GL_APICALL void (QOPENGLF_APIENTRYP CompressedTexSubImage2D)(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLsizei imageSize, const GLvoid *data);
     void (QOPENGLF_APIENTRYP CompressedTexSubImage3D)(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLsizei width, GLsizei height, GLsizei depth, GLenum format, GLsizei imageSize, const GLvoid *data);
     void (QOPENGLF_APIENTRYP CompressedTexImage1D)(GLenum target, GLint level, GLenum internalFormat, GLsizei width, GLint border, GLsizei imageSize, const GLvoid *data);
-    void (QOPENGLF_APIENTRYP CompressedTexImage2D)(GLenum target, GLint level, GLenum internalFormat, GLsizei width, GLsizei height, GLint border, GLsizei imageSize, const GLvoid *data);
+    GL_APICALL void (QOPENGLF_APIENTRYP CompressedTexImage2D)(GLenum target, GLint level, GLenum internalFormat, GLsizei width, GLsizei height, GLint border, GLsizei imageSize, const GLvoid *data);
     void (QOPENGLF_APIENTRYP CompressedTexImage3D)(GLenum target, GLint level, GLenum internalFormat, GLsizei width, GLsizei height, GLsizei depth, GLint border, GLsizei imageSize, const GLvoid *data);
-    void (QOPENGLF_APIENTRYP ActiveTexture)(GLenum texture);
+    GL_APICALL void (QOPENGLF_APIENTRYP ActiveTexture)(GLenum texture);
 
     // OpenGL 3.0
-    void (QOPENGLF_APIENTRYP GenerateMipmap)(GLenum target);
+    GL_APICALL void (QOPENGLF_APIENTRYP GenerateMipmap)(GLenum target);
 
     // OpenGL 3.2
     void (QOPENGLF_APIENTRYP TexImage3DMultisample)(GLenum target, GLsizei samples, GLint internalFormat, GLsizei width, GLsizei height, GLsizei depth, GLboolean fixedSampleLocations);
diff --git a/src/gui/opengl/qopenglvertexarrayobject.cpp b/src/gui/opengl/qopenglvertexarrayobject.cpp
index 6753064a60..babe52aa83 100644
--- a/src/gui/opengl/qopenglvertexarrayobject.cpp
+++ b/src/gui/opengl/qopenglvertexarrayobject.cpp
@@ -358,9 +358,11 @@ QOpenGLVertexArrayObject::~QOpenGLVertexArrayObject()
 
     Q_D(QOpenGLVertexArrayObject);
     QOpenGLContext *oldContext = 0;
+    QSurface *oldContextSurface = 0;
     QScopedPointer<QOffscreenSurface> offscreenSurface;
     if (d->context && ctx && d->context != ctx) {
         oldContext = ctx;
+        oldContextSurface = ctx->surface();
         // Cannot just make the current surface current again with another context.
         // The format may be incompatible and some platforms (iOS) may impose
         // restrictions on using a window with different contexts. Create an
@@ -380,7 +382,7 @@ QOpenGLVertexArrayObject::~QOpenGLVertexArrayObject()
         destroy();
 
     if (oldContext) {
-        if (!oldContext->makeCurrent(oldContext->surface()))
+        if (!oldContext->makeCurrent(oldContextSurface))
             qWarning("QOpenGLVertexArrayObject::~QOpenGLVertexArrayObject() failed to restore current context");
     }
 }