diff --git a/ext/random/engine_mt19937.c b/ext/random/engine_mt19937.c
index 1034fdf39a4cd..7723b5414d95f 100644
--- a/ext/random/engine_mt19937.c
+++ b/ext/random/engine_mt19937.c
@@ -86,7 +86,11 @@
 	SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
-#define N             MT_N                 /* length of state vector */
+#define N             624                 /* length of state vector */
+ZEND_STATIC_ASSERT(
+	N == sizeof(((php_random_status_state_mt19937*)0)->state) / sizeof(((php_random_status_state_mt19937*)0)->state[0]),
+	"Assumed length of Mt19937 state vector does not match actual size."
+);
 #define M             (397)                /* a period parameter */
 #define hiBit(u)      ((u) & 0x80000000U)  /* mask all but highest   bit of u */
 #define loBit(u)      ((u) & 0x00000001U)  /* mask all but lowest    bit of u */
@@ -130,7 +134,7 @@ PHPAPI inline void php_random_mt19937_seed32(php_random_status_state_mt19937 *st
 	   In previous versions, most significant bits (MSBs) of the seed affect
 	   only MSBs of the state array.  Modified 9 Jan 2002 by Makoto Matsumoto. */
 	state->state[0] = seed;
-	for (i = 1; i < MT_N; i++) {
+	for (i = 1; i < N; i++) {
 		prev_state = state->state[i - 1];
 		state->state[i] = (1812433253U * (prev_state  ^ (prev_state  >> 30)) + i) & 0xffffffffU;
 	}
@@ -144,7 +148,7 @@ static php_random_result generate(void *state)
 	php_random_status_state_mt19937 *s = state;
 	uint32_t s1;
 
-	if (s->count >= MT_N) {
+	if (s->count >= N) {
 		mt19937_reload(s);
 	}
 
@@ -172,7 +176,7 @@ static bool serialize(void *state, HashTable *data)
 	php_random_status_state_mt19937 *s = state;
 	zval t;
 
-	for (uint32_t i = 0; i < MT_N; i++) {
+	for (uint32_t i = 0; i < N; i++) {
 		ZVAL_STR(&t, php_random_bin2hex_le(&s->state[i], sizeof(uint32_t)));
 		zend_hash_next_index_insert(data, &t);
 	}
@@ -190,11 +194,11 @@ static bool unserialize(void *state, HashTable *data)
 	zval *t;
 
 	/* Verify the expected number of elements, this implicitly ensures that no additional elements are present. */
-	if (zend_hash_num_elements(data) != (MT_N + 2)) {
+	if (zend_hash_num_elements(data) != (N + 2)) {
 		return false;
 	}
 
-	for (uint32_t i = 0; i < MT_N; i++) {
+	for (uint32_t i = 0; i < N; i++) {
 		t = zend_hash_index_find(data, i);
 		if (!t || Z_TYPE_P(t) != IS_STRING || Z_STRLEN_P(t) != (2 * sizeof(uint32_t))) {
 			return false;
@@ -203,16 +207,16 @@ static bool unserialize(void *state, HashTable *data)
 			return false;
 		}
 	}
-	t = zend_hash_index_find(data, MT_N);
+	t = zend_hash_index_find(data, N);
 	if (!t || Z_TYPE_P(t) != IS_LONG) {
 		return false;
 	}
 	s->count = Z_LVAL_P(t);
-	if (s->count > MT_N) {
+	if (s->count > N) {
 		return false;
 	}
 
-	t = zend_hash_index_find(data, MT_N + 1);
+	t = zend_hash_index_find(data, N + 1);
 	if (!t || Z_TYPE_P(t) != IS_LONG) {
 		return false;
 	}
diff --git a/ext/random/php_random.h b/ext/random/php_random.h
index c62761029ddcf..e878914189606 100644
--- a/ext/random/php_random.h
+++ b/ext/random/php_random.h
@@ -45,10 +45,10 @@ PHPAPI double php_combined_lcg(void);
 
 # define PHP_MT_RAND_MAX ((zend_long) (0x7FFFFFFF)) /* (1<<31) - 1 */
 
-# define MT_RAND_MT19937 0
-# define MT_RAND_PHP 1
-
-# define MT_N (624)
+enum php_random_mt19937_mode {
+	MT_RAND_MT19937 = 0,
+	MT_RAND_PHP = 1,
+};
 
 #define PHP_RANDOM_RANGE_ATTEMPTS (50)
 
@@ -71,9 +71,9 @@ typedef struct _php_random_status_state_combinedlcg {
 } php_random_status_state_combinedlcg;
 
 typedef struct _php_random_status_state_mt19937 {
-	uint32_t state[MT_N];
 	uint32_t count;
-	uint8_t mode;
+	enum php_random_mt19937_mode mode;
+	uint32_t state[624];
 } php_random_status_state_mt19937;
 
 typedef struct _php_random_status_state_pcgoneseq128xslrr64 {