diff --git a/Tools/ardupilotwaf/boards.py b/Tools/ardupilotwaf/boards.py
index b3862c17d7..9fae4b12e1 100644
--- a/Tools/ardupilotwaf/boards.py
+++ b/Tools/ardupilotwaf/boards.py
@@ -170,6 +170,7 @@ class Board:
             '-Werror=unused-result',
             '-Werror=return-type',
             '-Werror=shadow',
+            '-Werror=unused-variable',
             '-Wfatal-errors',
             '-Wno-trigraphs',
         ]
@@ -411,7 +412,6 @@ class chibios(Board):
             '-Wno-unused-parameter',
             '-Werror=array-bounds',
             '-Wfatal-errors',
-            '-Werror=unused-variable',
             '-Werror=uninitialized',
             '-Werror=init-self',
             '-Wframe-larger-than=1024',