-Error out when trying to re-assign $this

diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
index 6d01268412bdc1275a0fa4d708c5fb0e4bdf1d99..969c15998b284572c9a7fb44c9663e807a9af895 100644 (file)
--- a/Zend/zend_compile.c
+++ b/Zend/zend_compile.c
@@ -487,6 +487,13 @@ void zend_do_assign(znode *result, znode *variable, znode *value TSRMLS_DC)
                SET_UNUSED(opline->result);
                *result = last_op->result;
        } else {
+               if (CG(active_class_entry) && (last_op->opcode == ZEND_FETCH_W) && (last_op->op1.op_type == IS_CONST)
+                       && (last_op->op1.u.constant.type == IS_STRING)
+                       && (last_op->op1.u.constant.value.str.len == (sizeof("this")-1))
+                       && !memcmp(last_op->op1.u.constant.value.str.val, "this", sizeof("this"))) {
+                       zend_error(E_COMPILE_ERROR, "Cannot re-assign $this");
+               }
+
                opline->opcode = ZEND_ASSIGN;
                opline->op1 = *variable;
                opline->op2 = *value;