diff --git a/tools/build/options/makeman b/tools/build/options/makeman
index f65c16cc1bc2..cb4d946816a7 100755
--- a/tools/build/options/makeman
+++ b/tools/build/options/makeman
@@ -3,6 +3,7 @@
 # This file is in the public domain.
 
 set -o errexit
+LC_ALL=C
 
 ident='$FreeBSD$'