From 89ca5aef9fbfe751bd1b4fa9213dee82612e9dd8 Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Thu, 23 Jan 2025 09:38:29 +1030
Subject: [PATCH] common: don't crash on send_backtrace() if bt_print is NULL.

This (and bt_exit) are NULL for libplugin.  We don't always want to crash!

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
 common/daemon.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/common/daemon.c b/common/daemon.c
index 31878a55d..c14de8b07 100644
--- a/common/daemon.c
+++ b/common/daemon.c
@@ -32,6 +32,9 @@ void send_backtrace(const char *why)
 	if (backtrace_state)
 		backtrace_print(backtrace_state, 0, stderr);
 
+	if (!bt_print)
+		return;
+
 	/* Now send to parent. */
 	bt_print("%s (version %s)", why, version());
 	if (backtrace_state)
@@ -75,7 +78,8 @@ static void crashdump(int sig)
 	send_backtrace(why);
 
 	/* Probably shouldn't return. */
-	bt_exit();
+	if (bt_exit)
+		bt_exit();
 
 	/* This time it will kill us instantly. */
 	kill(getpid(), sig);