From 6ebfa59331b7febf162d05eef8316b12d559de9b Mon Sep 17 00:00:00 2001
From: David Edmundson <kde@davidedmundson.co.uk>
Date: Fri, 5 Oct 2018 14:04:09 +0100
Subject: [PATCH 1/2] [plugins/qpa] Don't crash on Qt5.12 OpengGL::makeCurrent

Summary:
QOpenGLContext was changed to call platform->makeCurrent before it
called setCurrentContext.

Because we bind window FBO and ultimately that calls
QOpenGlContext::format we need Qt to know which context is current so it
can tell us the format.

This matches the QtWayland EGL code.

BUG: 399392

Test Plan:
Switched virtual desktop with the OSD (previously reliably crashed)
Now it doesn't

Reviewers: #kwin, zzag

Reviewed By: #kwin, zzag

Subscribers: zzag, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D15957
---
 plugins/qpa/sharingplatformcontext.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/plugins/qpa/sharingplatformcontext.cpp b/plugins/qpa/sharingplatformcontext.cpp
index 895da23b47..a318bf0795 100644
--- a/plugins/qpa/sharingplatformcontext.cpp
+++ b/plugins/qpa/sharingplatformcontext.cpp
@@ -26,6 +26,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <logging.h>
 
 #include <QOpenGLFramebufferObject>
+#include <private/qopenglcontext_p.h>
 
 namespace KWin
 {
@@ -48,6 +49,8 @@ SharingPlatformContext::SharingPlatformContext(QOpenGLContext *context, const EG
 bool SharingPlatformContext::makeCurrent(QPlatformSurface *surface)
 {
     Window *window = static_cast<Window*>(surface);
+
+    QOpenGLContextPrivate::setCurrentContext(context());
     if (eglMakeCurrent(eglDisplay(), m_surface, m_surface, eglContext())) {
         window->bindContentFBO();
         return true;

From 0b7778f964107436748db020c0e4ee6f09cc6c67 Mon Sep 17 00:00:00 2001
From: David Edmundson <kde@davidedmundson.co.uk>
Date: Fri, 5 Oct 2018 14:38:20 +0100
Subject: [PATCH 2/2] [plugins/qpa] Add explanatory comment

---
 plugins/qpa/sharingplatformcontext.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/plugins/qpa/sharingplatformcontext.cpp b/plugins/qpa/sharingplatformcontext.cpp
index a318bf0795..a6e4b2bd83 100644
--- a/plugins/qpa/sharingplatformcontext.cpp
+++ b/plugins/qpa/sharingplatformcontext.cpp
@@ -50,6 +50,8 @@ bool SharingPlatformContext::makeCurrent(QPlatformSurface *surface)
 {
     Window *window = static_cast<Window*>(surface);
 
+    // QOpenGLContext::makeCurrent in Qt5.12 calls platfrom->setContext before setCurrentContext
+    // but binding the content FBO looks up the format from the current context, so we need // to make sure sure Qt knows what the correct one is already
     QOpenGLContextPrivate::setCurrentContext(context());
     if (eglMakeCurrent(eglDisplay(), m_surface, m_surface, eglContext())) {
         window->bindContentFBO();