From 3179789f463e834c75a1e72ae06a22a562becbff Mon Sep 17 00:00:00 2001
From: Benoit Chesneau <bchesneau@gmail.com>
Date: Fri, 23 Jan 2026 21:25:07 +0100
Subject: [PATCH] fix: handle SIGCLD alias for SIGCHLD on Linux

On Linux, SIGCLD and SIGCHLD are aliases for the same signal number (17).
The SIG_NAMES dict iteration order can map to either name, causing
"Unhandled signal: cld" errors when workers fail during boot.

Fixes #3453
---
 gunicorn/arbiter.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/gunicorn/arbiter.py b/gunicorn/arbiter.py
index 222b3ca3..f8c64b4b 100644
--- a/gunicorn/arbiter.py
+++ b/gunicorn/arbiter.py
@@ -237,6 +237,10 @@ class Arbiter:
         """SIGCHLD handling - called from main loop, safe to log."""
         self.reap_workers()
 
+    # SIGCLD is an alias for SIGCHLD on Linux. The SIG_NAMES dict may map
+    # to either "chld" or "cld" depending on iteration order of dir(signal).
+    handle_cld = handle_chld
+
     def handle_hup(self):
         """\
         HUP handling.