diff --git a/ext/spl/spl_array.c b/ext/spl/spl_array.c
index f6a11e7231d..e5d97141684 100644
--- a/ext/spl/spl_array.c
+++ b/ext/spl/spl_array.c
@@ -1304,7 +1304,7 @@ PHP_METHOD(ArrayObject, count)
 	RETURN_LONG(spl_array_object_count_elements_helper(intern));
 } /* }}} */
 
-static void spl_array_method(INTERNAL_FUNCTION_PARAMETERS, char *fname, int fname_len, int use_arg) /* {{{ */
+static void spl_array_method(INTERNAL_FUNCTION_PARAMETERS, char *fname, size_t fname_len, int use_arg) /* {{{ */
 {
 	spl_array_object *intern = Z_SPLARRAY_P(ZEND_THIS);
 	HashTable **ht_ptr = spl_array_get_hash_table_ptr(intern);
@@ -1393,12 +1393,12 @@ PHP_METHOD(ArrayIterator, current)
 	}
 
 	if ((entry = zend_hash_get_current_data_ex(aht, spl_array_get_pos_ptr(aht, intern))) == NULL) {
-		return;
+		RETURN_NULL();
 	}
 	if (Z_TYPE_P(entry) == IS_INDIRECT) {
 		entry = Z_INDIRECT_P(entry);
 		if (Z_TYPE_P(entry) == IS_UNDEF) {
-			return;
+			RETURN_NULL();
 		}
 	}
 	RETURN_COPY_DEREF(entry);
@@ -1490,7 +1490,7 @@ PHP_METHOD(RecursiveArrayIterator, getChildren)
 	}
 
 	if ((entry = zend_hash_get_current_data_ex(aht, spl_array_get_pos_ptr(aht, intern))) == NULL) {
-		return;
+		RETURN_NULL();
 	}
 
 	if (Z_TYPE_P(entry) == IS_INDIRECT) {
@@ -1500,7 +1500,7 @@ PHP_METHOD(RecursiveArrayIterator, getChildren)
 	ZVAL_DEREF(entry);
 	if (Z_TYPE_P(entry) == IS_OBJECT) {
 		if ((intern->ar_flags & SPL_ARRAY_CHILD_ARRAYS_ONLY) != 0) {
-			return;
+			RETURN_NULL();
 		}
 		if (instanceof_function(Z_OBJCE_P(entry), Z_OBJCE_P(ZEND_THIS))) {
 			RETURN_OBJ_COPY(Z_OBJ_P(entry));
diff --git a/ext/spl/spl_dllist.c b/ext/spl/spl_dllist.c
index 0daf486e40b..5fd3830014a 100644
--- a/ext/spl/spl_dllist.c
+++ b/ext/spl/spl_dllist.c
@@ -1215,7 +1215,7 @@ PHP_METHOD(SplDoublyLinkedList, add)
 PHP_METHOD(SplDoublyLinkedList, __debugInfo)
 {
 	if (zend_parse_parameters_none() == FAILURE) {
-		return;
+		RETURN_THROWS();
 	}
 
 	RETURN_ARR(spl_dllist_object_get_debug_info(Z_OBJ_P(ZEND_THIS)));
diff --git a/ext/spl/spl_fixedarray.c b/ext/spl/spl_fixedarray.c
index 9fdbc34cb7f..5f8dca8dd18 100644
--- a/ext/spl/spl_fixedarray.c
+++ b/ext/spl/spl_fixedarray.c
@@ -781,7 +781,7 @@ PHP_METHOD(SplFixedArray, offsetUnset)
 PHP_METHOD(SplFixedArray, getIterator)
 {
 	if (zend_parse_parameters_none() == FAILURE) {
-		return;
+		RETURN_THROWS();
 	}
 
 	zend_create_internal_iterator_zval(return_value, ZEND_THIS);
diff --git a/ext/spl/spl_functions.c b/ext/spl/spl_functions.c
index 0f46c2e8b18..0fcf3896673 100644
--- a/ext/spl/spl_functions.c
+++ b/ext/spl/spl_functions.c
@@ -19,8 +19,6 @@
 #endif
 
 #include "php.h"
-#include "php_ini.h"
-#include "ext/standard/info.h"
 #include "php_spl.h"
 
 /* {{{ spl_add_class_name */
@@ -41,11 +39,9 @@ void spl_add_class_name(zval *list, zend_class_entry *pce, int allow, int ce_fla
 /* {{{ spl_add_interfaces */
 void spl_add_interfaces(zval *list, zend_class_entry * pce, int allow, int ce_flags)
 {
-	uint32_t num_interfaces;
-
 	if (pce->num_interfaces) {
 		ZEND_ASSERT(pce->ce_flags & ZEND_ACC_LINKED);
-		for (num_interfaces = 0; num_interfaces < pce->num_interfaces; num_interfaces++) {
+		for (uint32_t num_interfaces = 0; num_interfaces < pce->num_interfaces; num_interfaces++) {
 			spl_add_class_name(list, pce->interfaces[num_interfaces], allow, ce_flags);
 		}
 	}
@@ -55,10 +51,9 @@ void spl_add_interfaces(zval *list, zend_class_entry * pce, int allow, int ce_fl
 /* {{{ spl_add_traits */
 void spl_add_traits(zval *list, zend_class_entry * pce, int allow, int ce_flags)
 {
-	uint32_t num_traits;
 	zend_class_entry *trait;
 
-	for (num_traits = 0; num_traits < pce->num_traits; num_traits++) {
+	for (uint32_t num_traits = 0; num_traits < pce->num_traits; num_traits++) {
 		trait = zend_fetch_class_by_name(pce->trait_names[num_traits].name,
 			pce->trait_names[num_traits].lc_name, ZEND_FETCH_CLASS_TRAIT);
 		ZEND_ASSERT(trait);
@@ -69,11 +64,9 @@ void spl_add_traits(zval *list, zend_class_entry * pce, int allow, int ce_flags)
 
 
 /* {{{ spl_add_classes */
-int spl_add_classes(zend_class_entry *pce, zval *list, int sub, int allow, int ce_flags)
+void spl_add_classes(zend_class_entry *pce, zval *list, bool sub, int allow, int ce_flags)
 {
-	if (!pce) {
-		return 0;
-	}
+	ZEND_ASSERT(pce);
 	spl_add_class_name(list, pce, allow, ce_flags);
 	if (sub) {
 		spl_add_interfaces(list, pce, allow, ce_flags);
@@ -82,11 +75,10 @@ int spl_add_classes(zend_class_entry *pce, zval *list, int sub, int allow, int c
 			spl_add_classes(pce, list, sub, allow, ce_flags);
 		}
 	}
-	return 0;
 }
 /* }}} */
 
-zend_string * spl_gen_private_prop_name(zend_class_entry *ce, char *prop_name, int prop_len) /* {{{ */
+zend_string * spl_gen_private_prop_name(zend_class_entry *ce, char *prop_name, size_t prop_len) /* {{{ */
 {
 	return zend_mangle_property_name(ZSTR_VAL(ce->name), ZSTR_LEN(ce->name), prop_name, prop_len, 0);
 }
diff --git a/ext/spl/spl_functions.h b/ext/spl/spl_functions.h
index e6c3171c34f..20eb323c5fe 100644
--- a/ext/spl/spl_functions.h
+++ b/ext/spl/spl_functions.h
@@ -32,9 +32,9 @@ typedef zend_object* (*create_object_func_t)(zend_class_entry *class_type);
 void spl_add_class_name(zval * list, zend_class_entry * pce, int allow, int ce_flags);
 void spl_add_interfaces(zval * list, zend_class_entry * pce, int allow, int ce_flags);
 void spl_add_traits(zval * list, zend_class_entry * pce, int allow, int ce_flags);
-int spl_add_classes(zend_class_entry *pce, zval *list, int sub, int allow, int ce_flags);
+void spl_add_classes(zend_class_entry *pce, zval *list, bool sub, int allow, int ce_flags);
 
 /* caller must efree(return) */
-zend_string *spl_gen_private_prop_name(zend_class_entry *ce, char *prop_name, int prop_len);
+zend_string *spl_gen_private_prop_name(zend_class_entry *ce, char *prop_name, size_t prop_len);
 
 #endif /* PHP_FUNCTIONS_H */
diff --git a/ext/spl/spl_heap.c b/ext/spl/spl_heap.c
index bb874e47dc8..3112666e336 100644
--- a/ext/spl/spl_heap.c
+++ b/ext/spl/spl_heap.c
@@ -1053,7 +1053,7 @@ PHP_METHOD(SplPriorityQueue, current)
 PHP_METHOD(SplHeap, __debugInfo)
 {
 	if (zend_parse_parameters_none() == FAILURE) {
-		return;
+		RETURN_THROWS();
 	}
 
 	RETURN_ARR(spl_heap_object_get_debug_info(spl_ce_SplHeap, Z_OBJ_P(ZEND_THIS)));
@@ -1063,7 +1063,7 @@ PHP_METHOD(SplHeap, __debugInfo)
 PHP_METHOD(SplPriorityQueue, __debugInfo)
 {
 	if (zend_parse_parameters_none() == FAILURE) {
-		return;
+		RETURN_THROWS();
 	}
 
 	RETURN_ARR(spl_heap_object_get_debug_info(spl_ce_SplPriorityQueue, Z_OBJ_P(ZEND_THIS)));
diff --git a/ext/spl/spl_iterators.c b/ext/spl/spl_iterators.c
index 217f3aa19c0..fee682a945a 100644
--- a/ext/spl/spl_iterators.c
+++ b/ext/spl/spl_iterators.c
@@ -870,7 +870,7 @@ PHP_METHOD(RecursiveIteratorIterator, callGetChildren)
 
 	zobject = &object->iterators[object->level].zobject;
 	if (Z_TYPE_P(zobject) == IS_UNDEF) {
-		return;
+		RETURN_NULL();
 	} else {
 		zend_call_method_with_0_params(Z_OBJ_P(zobject), ce, &object->iterators[object->level].getchildren, "getchildren", return_value);
 		if (Z_TYPE_P(return_value) == IS_UNDEF) {
diff --git a/ext/spl/spl_observer.c b/ext/spl/spl_observer.c
index 3ac375c5cd6..4c6cef6cb06 100644
--- a/ext/spl/spl_observer.c
+++ b/ext/spl/spl_observer.c
@@ -82,7 +82,7 @@ void spl_SplObjectStorage_free_storage(zend_object *object) /* {{{ */
 	zend_hash_destroy(&intern->storage);
 } /* }}} */
 
-static int spl_object_storage_get_hash(zend_hash_key *key, spl_SplObjectStorage *intern, zend_object *obj) {
+static zend_result spl_object_storage_get_hash(zend_hash_key *key, spl_SplObjectStorage *intern, zend_object *obj) {
 	if (UNEXPECTED(intern->fptr_get_hash)) {
 		zval param;
 		zval rv;
@@ -218,12 +218,12 @@ spl_SplObjectStorageElement *spl_object_storage_attach(spl_SplObjectStorage *int
 	return pelement;
 } /* }}} */
 
-static int spl_object_storage_detach(spl_SplObjectStorage *intern, zend_object *obj) /* {{{ */
+static zend_result spl_object_storage_detach(spl_SplObjectStorage *intern, zend_object *obj) /* {{{ */
 {
 	if (EXPECTED(!(intern->flags & SOS_OVERRIDDEN_UNSET_DIMENSION))) {
 		return zend_hash_index_del(&intern->storage, obj->handle);
 	}
-	int ret = FAILURE;
+	zend_result ret = FAILURE;
 	zend_hash_key key;
 	if (spl_object_storage_get_hash(&key, intern, obj) == FAILURE) {
 		return ret;
@@ -544,7 +544,7 @@ PHP_METHOD(SplObjectStorage, offsetGet)
 	ZEND_PARSE_PARAMETERS_END();
 
 	if (spl_object_storage_get_hash(&key, intern, obj) == FAILURE) {
-		return;
+		RETURN_NULL();
 	}
 
 	element = spl_object_storage_get(intern, &key);
@@ -723,7 +723,7 @@ PHP_METHOD(SplObjectStorage, getInfo)
 	}
 
 	if ((element = zend_hash_get_current_data_ptr_ex(&intern->storage, &intern->pos)) == NULL) {
-		return;
+		RETURN_NULL();
 	}
 	ZVAL_COPY(return_value, &element->inf);
 } /* }}} */
@@ -740,7 +740,7 @@ PHP_METHOD(SplObjectStorage, setInfo)
 	}
 
 	if ((element = zend_hash_get_current_data_ptr_ex(&intern->storage, &intern->pos)) == NULL) {
-		return;
+		RETURN_NULL();
 	}
 	zval_ptr_dtor(&element->inf);
 	ZVAL_COPY(&element->inf, inf);
@@ -1008,7 +1008,7 @@ PHP_METHOD(SplObjectStorage, __unserialize)
 PHP_METHOD(SplObjectStorage, __debugInfo)
 {
 	if (zend_parse_parameters_none() == FAILURE) {
-		return;
+		RETURN_THROWS();
 	}
 
 	RETURN_ARR(spl_object_storage_debug_info(Z_OBJ_P(ZEND_THIS)));