Added deprecated notice for cases where the behavior will change

Author: pmmaga

Zend/zend_hash.c

@@ -789,6 +789,14 @@ static zend_always_inline zval *_zend_hash_index_add_or_update_i(HashTable *ht,
 	IS_CONSISTENT(ht);
 	HT_ASSERT_RC1(ht);
 
+	/* Removing this block will end the deprecation phase and allow the new behavior */
+	if (UNEXPECTED(flag & HASH_ADD_NEXT
+		&& ht->nNextFreeElement > ZEND_LONG_MIN 
+		&& ht->nNextFreeElement < 0)) {
+		zend_error(E_DEPRECATED, "In the next major version of PHP the implicit keys of this array will start from %d instead of 0", ht->nNextFreeElement);
+		h = 0;
+	}
+
 	if (h == ZEND_LONG_MIN && flag & HASH_ADD_NEXT) {
 		h = 0;
 	}

ext/standard/tests/array/array_fill_variation1.phpt

@@ -117,10 +117,12 @@ array(2) {
   int(100)
 }
 -- Iteration 2 --
+
+Deprecated: In the next major version of PHP the implicit keys of this array will start from -9 instead of 0 in %s
 array(2) {
   [-10]=>
   int(100)
-  [-9]=>
+  [0]=>
   int(100)
 }
 -- Iteration 3 --

ext/standard/tests/array/array_fill_variation1_64bit.phpt

@@ -117,10 +117,12 @@ array(2) {
   int(100)
 }
 -- Iteration 2 --
+
+Deprecated: In the next major version of PHP the implicit keys of this array will start from -9 instead of 0 in %s
 array(2) {
   [-10]=>
   int(100)
-  [-9]=>
+  [0]=>
   int(100)
 }
 -- Iteration 3 --

ext/standard/tests/array/bug67693.phpt

@@ -14,12 +14,13 @@ var_dump($array);
 
 echo"\nDone";
 ?>
---EXPECT--
+--EXPECTF--
+Deprecated: In the next major version of PHP the implicit keys of this array will start from -1 instead of 0 in %s
 array(2) {
-  [-1]=>
-  int(0)
   [0]=>
   int(0)
+  [1]=>
+  int(0)
 }
 
 Done

ext/standard/tests/array/count_recursive.phpt

@@ -130,6 +130,7 @@ fclose( $resource1 );
 closedir( $resource2 );
 ?>
 --EXPECTF--
+Deprecated: In the next major version of PHP the implicit keys of this array will start from -1 instead of 0 in %s
 *** Testing basic functionality of count() function ***
 -- Testing NULL --