diff --git a/ci/check_gucs_are_alphabetically_sorted.sh b/ci/check_gucs_are_alphabetically_sorted.sh
index 214a5c9cf..018fc7d35 100755
--- a/ci/check_gucs_are_alphabetically_sorted.sh
+++ b/ci/check_gucs_are_alphabetically_sorted.sh
@@ -20,6 +20,6 @@ tail -n +$RegisterCitusConfigVariables_begin_linenumber src/backend/distributed/
 
 # extract citus gucs in the form of <tab><tab>"citus.X"
 grep -P "^[\t][\t]\"citus\.[a-zA-Z_0-9]+\"" RegisterCitusConfigVariables_func_def.out > gucs.out
-sort -c gucs.out
+LC_COLLATE=C sort -c gucs.out
 rm gucs.out
 rm RegisterCitusConfigVariables_func_def.out