From 22777e548061d4731bce98cbebefde6d18d15b25 Mon Sep 17 00:00:00 2001
From: ed <eddavies95@gmail.com>
Date: Fri, 12 Mar 2021 10:28:14 +0000
Subject: [PATCH] Linux:  Remove embedded OpenGL window events from event queue
 when destroying

This fixes BadWindow errors from Expose events that may be processed after the window is destroyed.
---
 modules/juce_opengl/native/juce_OpenGL_linux_X11.h | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/modules/juce_opengl/native/juce_OpenGL_linux_X11.h b/modules/juce_opengl/native/juce_OpenGL_linux_X11.h
index ef7eb852ed..1219041323 100644
--- a/modules/juce_opengl/native/juce_OpenGL_linux_X11.h
+++ b/modules/juce_opengl/native/juce_OpenGL_linux_X11.h
@@ -97,7 +97,7 @@ public:
         XSetWindowAttributes swa;
         swa.colormap = colourMap;
         swa.border_pixel = 0;
-        swa.event_mask = ExposureMask | StructureNotifyMask;
+        swa.event_mask = embeddedWindowEventMask;
 
         auto glBounds = component.getTopLevelComponent()
                            ->getLocalArea (&component, component.getLocalBounds());
@@ -133,9 +133,18 @@ public:
             if (embeddedWindow != 0)
             {
                 XWindowSystemUtilities::ScopedXLock xLock;
+
                 X11Symbols::getInstance()->xUnmapWindow (display, embeddedWindow);
                 X11Symbols::getInstance()->xDestroyWindow (display, embeddedWindow);
                 X11Symbols::getInstance()->xSync (display, False);
+
+                XEvent event;
+                while (X11Symbols::getInstance()->xCheckWindowEvent (display,
+                                                                     embeddedWindow,
+                                                                     embeddedWindowEventMask,
+                                                                     &event) == True)
+                {
+                }
             }
         }
 
@@ -233,6 +242,8 @@ public:
     struct Locker { Locker (NativeContext&) {} };
 
 private:
+    static constexpr int embeddedWindowEventMask = ExposureMask | StructureNotifyMask;
+
     Component& component;
     GLXContext renderContext = {};
     Window embeddedWindow = {};