Add missing resource key warning for unset()

It was present on other operations, including isset(), but was
missing for unset().

Author: nikic

Zend/tests/resource_key.phpt

@@ -0,0 +1,36 @@
+--TEST--
+Behavior of resources as array keys
+--FILE--
+<?php
+
+$r = fopen(__FILE__, 'r');
+$a = [];
+echo "Assign:";
+$a[$r] = 1;
+echo "Add assign:";
+$a[$r] += 1;
+echo "Inc:";
+$a[$r]++;
+echo "Get:";
+var_dump($a[$r]);
+echo "Isset:";
+var_dump(isset($a[$r]));
+echo "Unset:";
+unset($a[$r]);
+
+?>
+--EXPECTF--
+Assign:
+Warning: Resource ID#%d used as offset, casting to integer (%d) in %s on line %d
+Add assign:
+Warning: Resource ID#%d used as offset, casting to integer (%d) in %s on line %d
+Inc:
+Warning: Resource ID#%d used as offset, casting to integer (%d) in %s on line %d
+Get:
+Warning: Resource ID#%d used as offset, casting to integer (%d) in %s on line %d
+int(3)
+Isset:
+Warning: Resource ID#%d used as offset, casting to integer (%d) in %s on line %d
+bool(true)
+Unset:
+Warning: Resource ID#%d used as offset, casting to integer (%d) in %s on line %d

Zend/zend_vm_def.h

@@ -6396,6 +6396,7 @@ ZEND_VM_C_LABEL(num_index_dim):
 				hval = 1;
 				ZEND_VM_C_GOTO(num_index_dim);
 			} else if (Z_TYPE_P(offset) == IS_RESOURCE) {
+				zend_use_resource_as_offset(offset);
 				hval = Z_RES_HANDLE_P(offset);
 				ZEND_VM_C_GOTO(num_index_dim);
 			} else if (OP2_TYPE == IS_CV && Z_TYPE_P(offset) == IS_UNDEF) {

Zend/zend_vm_execute.h

@@ -24382,6 +24382,7 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_UNSET_DIM_SPEC_VAR_CONST_HANDL
 				hval = 1;
 				goto num_index_dim;
 			} else if (Z_TYPE_P(offset) == IS_RESOURCE) {
+				zend_use_resource_as_offset(offset);
 				hval = Z_RES_HANDLE_P(offset);
 				goto num_index_dim;
 			} else if (IS_CONST == IS_CV && Z_TYPE_P(offset) == IS_UNDEF) {
@@ -26532,6 +26533,7 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_UNSET_DIM_SPEC_VAR_TMPVAR_HAND
 				hval = 1;
 				goto num_index_dim;
 			} else if (Z_TYPE_P(offset) == IS_RESOURCE) {
+				zend_use_resource_as_offset(offset);
 				hval = Z_RES_HANDLE_P(offset);
 				goto num_index_dim;
 			} else if ((IS_TMP_VAR|IS_VAR) == IS_CV && Z_TYPE_P(offset) == IS_UNDEF) {
@@ -30543,6 +30545,7 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_UNSET_DIM_SPEC_VAR_CV_HANDLER(
 				hval = 1;
 				goto num_index_dim;
 			} else if (Z_TYPE_P(offset) == IS_RESOURCE) {
+				zend_use_resource_as_offset(offset);
 				hval = Z_RES_HANDLE_P(offset);
 				goto num_index_dim;
 			} else if (IS_CV == IS_CV && Z_TYPE_P(offset) == IS_UNDEF) {
@@ -41807,6 +41810,7 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_UNSET_DIM_SPEC_CV_CONST_HANDLE
 				hval = 1;
 				goto num_index_dim;
 			} else if (Z_TYPE_P(offset) == IS_RESOURCE) {
+				zend_use_resource_as_offset(offset);
 				hval = Z_RES_HANDLE_P(offset);
 				goto num_index_dim;
 			} else if (IS_CONST == IS_CV && Z_TYPE_P(offset) == IS_UNDEF) {
@@ -45250,6 +45254,7 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_UNSET_DIM_SPEC_CV_TMPVAR_HANDL
 				hval = 1;
 				goto num_index_dim;
 			} else if (Z_TYPE_P(offset) == IS_RESOURCE) {
+				zend_use_resource_as_offset(offset);
 				hval = Z_RES_HANDLE_P(offset);
 				goto num_index_dim;
 			} else if ((IS_TMP_VAR|IS_VAR) == IS_CV && Z_TYPE_P(offset) == IS_UNDEF) {
@@ -50372,6 +50377,7 @@ static ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL ZEND_UNSET_DIM_SPEC_CV_CV_HANDLER(Z
 				hval = 1;
 				goto num_index_dim;
 			} else if (Z_TYPE_P(offset) == IS_RESOURCE) {
+				zend_use_resource_as_offset(offset);
 				hval = Z_RES_HANDLE_P(offset);
 				goto num_index_dim;
 			} else if (IS_CV == IS_CV && Z_TYPE_P(offset) == IS_UNDEF) {