From 4df5129529b1af57d04a51f09145da5079822c3e Mon Sep 17 00:00:00 2001
From: Drew Weymouth <dweymouth@users.noreply.github.com>
Date: Sat, 6 Sep 2025 07:33:27 -0700
Subject: [PATCH] X11: check crtcInfo for NULL when polling monitors

---
 CONTRIBUTORS.md   | 1 +
 README.md         | 1 +
 src/x11_monitor.c | 5 +++++
 3 files changed, 7 insertions(+)

diff --git a/CONTRIBUTORS.md b/CONTRIBUTORS.md
index e3956e61d..0e1d88342 100644
--- a/CONTRIBUTORS.md
+++ b/CONTRIBUTORS.md
@@ -287,6 +287,7 @@ video tutorials.
  - Xo Wang
  - Andre Weissflog
  - Jay Weisskopf
+ - Drew Weymouth
  - Frank Wille
  - Andy Williams
  - Joel Winarske
diff --git a/README.md b/README.md
index 5e882e277..586d6be25 100644
--- a/README.md
+++ b/README.md
@@ -145,6 +145,7 @@ information on what to include when reporting a bug.
  - [Wayland] Bugfix: The cursor position was not updated when clicking through
    from a modal to the content area
  - [X11] Bugfix: Running without a WM could trigger an assert (#2593,#2601,#2631)
+ - [X11] Bugfix: Occasional crash when an idle display awakes (#2766) 
  - [Null] Added Vulkan 'window' surface creation via `VK_EXT_headless_surface`
  - [Null] Added EGL context creation on Mesa via `EGL_MESA_platform_surfaceless`
  - [EGL] Allowed native access on Wayland with `GLFW_CONTEXT_CREATION_API` set to
diff --git a/src/x11_monitor.c b/src/x11_monitor.c
index 3af827520..74c57ed01 100644
--- a/src/x11_monitor.c
+++ b/src/x11_monitor.c
@@ -151,6 +151,11 @@ void _glfwPollMonitorsX11(void)
             }
 
             XRRCrtcInfo* ci = XRRGetCrtcInfo(_glfw.x11.display, sr, oi->crtc);
+            if (!ci) {
+                XRRFreeOutputInfo(oi);
+                continue;
+            }
+
             if (ci->rotation == RR_Rotate_90 || ci->rotation == RR_Rotate_270)
             {
                 widthMM  = oi->mm_height;