diff --git a/uwsgiconfig.py b/uwsgiconfig.py
index 26a5297a5..8fe31ccb1 100644
--- a/uwsgiconfig.py
+++ b/uwsgiconfig.py
@@ -684,6 +684,7 @@ def __init__(self, filename, mute=False):
             '-I.',
             '-Wall',
             '-Werror',
+            '-Wformat-signedness',
             '-Wno-error=deprecated-declarations',
             '-D_LARGEFILE_SOURCE',
             '-D_FILE_OFFSET_BITS=64'