Fix null static_variable_ptr for uncalled fake closures

Closes GH-8083
Closes GH-8109

NEWS

@@ -5,6 +5,8 @@ PHP                                                                        NEWS
 - Core:
   . Fixed Haiku ZTS build. (David Carlier)
   . Fixed bug GH-8059 arginfo not regenerated for extension. (Remi)
+  . Fixed bug GH-8083 Segfault when dumping uncalled fake closure with static
+    variables. (ilutov)
 
 - GD:
   . Fixed libpng warning when loading interlaced images. (Brett)

Zend/tests/gh8083.phpt

@@ -0,0 +1,22 @@
+--TEST--
+GH-8083 (var_dump() on closure with static variable segfaults)
+--FILE--
+<?php
+
+function func() {
+    static $i;
+}
+
+$x = func(...);
+
+var_dump($x);
+
+?>
+--EXPECT--
+object(Closure)#1 (1) {
+  ["static"]=>
+  array(1) {
+    ["i"]=>
+    NULL
+  }
+}

Zend/zend_closures.c

@@ -697,6 +697,13 @@ static void zend_create_closure_ex(zval *res, zend_function *func, zend_class_en
 			}
 			ZEND_MAP_PTR_INIT(closure->func.op_array.static_variables_ptr,
 				&closure->func.op_array.static_variables);
+		} else if (func->op_array.static_variables) {
+			HashTable *ht = ZEND_MAP_PTR_GET(func->op_array.static_variables_ptr);
+
+			if (!ht) {
+				ht = zend_array_dup(func->op_array.static_variables);
+				ZEND_MAP_PTR_SET(closure->func.op_array.static_variables_ptr, ht);
+			}
 		}
 
 		/* Runtime cache is scope-dependent, so we cannot reuse it if the scope changed */