diff --git a/include/cglm/struct/mat2.h b/include/cglm/struct/mat2.h
index 7b2de89..c73f13c 100644
--- a/include/cglm/struct/mat2.h
+++ b/include/cglm/struct/mat2.h
@@ -59,7 +59,7 @@
  */
 CGLM_INLINE
 mat2s
-glms_mat2_identity() {
+glms_mat2_identity(void) {
   mat2s r;
   glm_mat2_identity(r.raw);
   return r;
@@ -91,7 +91,7 @@ glms_mat2_identity_array(mat2s * __restrict mat, size_t count) {
  */
 CGLM_INLINE
 mat2s
-glms_mat2_zero() {
+glms_mat2_zero(void) {
   mat2s r;
   glm_mat2_zero(r.raw);
   return r;
diff --git a/test/src/test_common.c b/test/src/test_common.c
index c352c89..46b6e63 100644
--- a/test/src/test_common.c
+++ b/test/src/test_common.c
@@ -47,7 +47,7 @@ test_rand_vec3(vec3 dest) {
 }
 
 vec3s
-test_rand_vec3s() {
+test_rand_vec3s(void) {
   vec3s r;
   test_rand_vec3(r.raw);
   return r;
@@ -62,7 +62,7 @@ test_rand_vec4(vec4 dest) {
 }
 
 vec4s
-test_rand_vec4s() {
+test_rand_vec4s(void) {
   vec4s r;
   test_rand_vec4(r.raw);
   return r;