Fix ksort(..., SORT_REGULAR) behaviour on arrays with numeric and string keys

The comparator function used at ksort in SORT_REGULAR mode
need to be consistent with basic comparison rules. These rules
were changed in PHP-8.0 for numeric strings, but comparator
used at ksort kept the old behaviour. It leads to inconsistent
situations, when after ksort the first key is GREATER than some
of the next ones by according to the basic comparison operators.

Author: DrDet

ext/standard/array.c

@@ -166,40 +166,20 @@ static zend_never_inline ZEND_COLD int stable_sort_fallback(Bucket *a, Bucket *b
 
 static zend_always_inline int php_array_key_compare_unstable_i(Bucket *f, Bucket *s) /* {{{ */
 {
-	zend_uchar t;
-	zend_long l1, l2;
-	double d;
-
-	if (f->key == NULL) {
-		if (s->key == NULL) {
-			return (zend_long)f->h > (zend_long)s->h ? 1 : -1;
-		} else {
-			l1 = (zend_long)f->h;
-			t = is_numeric_string(s->key->val, s->key->len, &l2, &d, 1);
-			if (t == IS_LONG) {
-				/* pass */
-			} else if (t == IS_DOUBLE) {
-				return ZEND_NORMALIZE_BOOL((double)l1 - d);
-			} else {
-				l2 = 0;
-			}
-		}
-	} else {
-		if (s->key) {
-			return zendi_smart_strcmp(f->key, s->key);
-		} else {
-			l2 = (zend_long)s->h;
-			t = is_numeric_string(f->key->val, f->key->len, &l1, &d, 1);
-			if (t == IS_LONG) {
-				/* pass */
-			} else if (t == IS_DOUBLE) {
-				return ZEND_NORMALIZE_BOOL(d - (double)l2);
-			} else {
-				l1 = 0;
-			}
-		}
-	}
-	return ZEND_NORMALIZE_BOOL(l1 - l2);
+    zval first;
+    zval second;
+
+    if (f->key) {
+        ZVAL_STR(&first, f->key);
+    } else {
+        ZVAL_LONG(&first, f->h);
+    }
+    if (s->key) {
+        ZVAL_STR(&second, s->key);
+    } else {
+        ZVAL_LONG(&second, s->h);
+    }
+    return zend_compare(&first, &second);
 }
 /* }}} */