diff --git a/src/Make.sh b/src/Make.sh
index a76f7d5ac1..83880780ec 100644
--- a/src/Make.sh
+++ b/src/Make.sh
@@ -5,6 +5,12 @@
 #         sh Make.sh Makefile.shlib
 #         sh Make.sh Makefile.list
 
+# turn off enforced customizations
+GREP_OPTIONS=
+# enforce using portable C locale
+LC_ALL=C
+export LC_ALL GREP_OPTIONS
+
 # function to create one style_*.h file
 # must whack *.d files that depend on style_*.h file,
 # else Make will not recreate them