diff --git a/t/t_openpam_ctype.c b/t/t_openpam_ctype.c
index 7e56f95..e97a446 100644
--- a/t/t_openpam_ctype.c
+++ b/t/t_openpam_ctype.c
@@ -94,7 +94,7 @@ T_OC(pfcs)
  * Boilerplate
  */
 
-const struct t_test *t_plan[] = {
+static const struct t_test *t_plan[] = {
 	T(t_oc_digit),
 	T(t_oc_xdigit),
 	T(t_oc_upper),
diff --git a/t/t_openpam_readlinev.c b/t/t_openpam_readlinev.c
index 82ae047..a644abd 100644
--- a/t/t_openpam_readlinev.c
+++ b/t/t_openpam_readlinev.c
@@ -288,7 +288,7 @@ T_FUNC(unterminated_line, "unterminated line")
  * Boilerplate
  */
 
-const struct t_test *t_plan[] = {
+static const struct t_test *t_plan[] = {
 	T(empty_input),
 	T(empty_line),
 	T(unterminated_empty_line),
diff --git a/t/t_openpam_readword.c b/t/t_openpam_readword.c
index 7f34030..f45c40d 100644
--- a/t/t_openpam_readword.c
+++ b/t/t_openpam_readword.c
@@ -947,7 +947,7 @@ T_FUNC(line_continuation_within_word, "line continuation within word")
  * Boilerplate
  */
 
-const struct t_test *t_plan[] = {
+static const struct t_test *t_plan[] = {
 	T(empty_input),
 	T(empty_line),
 	T(unterminated_line),