From: Doug Gilmore <dougjgilmore@gmail.com>
Date: Wed, 19 Aug 2020 12:04:46 +0000 (+0200)
Subject: Fix a segfault in daemon mode Emacs when detaching an X session
X-Git-Tag: emacs-28.0.90~6508
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=a7291a9fb979e117c3286d3cfa6d0d15557edace;p=emacs.git

Fix a segfault in daemon mode Emacs when detaching an X session

* src/xterm.c (x_uncatch_errors): Add a sanity check for
x_error_message (bug#23939).
---

diff --git a/src/xterm.c b/src/xterm.c
index 2a99c469276..2e0407aff40 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -9921,6 +9921,13 @@ x_uncatch_errors (void)
 {
   struct x_error_message_stack *tmp;
 
+  /* In rare situations when running Emacs run in daemon mode,
+     shutting down an emacsclient via delete-frame can cause
+     x_uncatch_errors to be called when x_error_message is set to
+     NULL.  */
+  if (x_error_message == NULL)
+    return;
+
   block_input ();
 
   /* The display may have been closed before this function is called.