From a6f7c6d847db3327c3432ca8c353fa3ec284b3d2 Mon Sep 17 00:00:00 2001
From: belliash <belliash@codingworkshop.eu.org>
Date: Wed, 29 May 2019 13:45:38 +0200
Subject: [PATCH] Prevent $base, $parent and $this from being unset.

---
 engine/vm.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/engine/vm.c b/engine/vm.c
index 8bcb080..d23e942 100644
--- a/engine/vm.c
+++ b/engine/vm.c
@@ -7580,6 +7580,10 @@ static int vm_builtin_unset(ph7_context *pCtx, int nArg, ph7_value **apArg) {
 				PH7_VmThrowError(pCtx->pVm, PH7_CTX_ERR, "Expecting a variable not a constant");
 			}
 		} else {
+			if(pObj->iFlags != MEMOBJ_VARIABLE) {
+				/* Throw an error */
+				PH7_VmThrowError(pCtx->pVm, PH7_CTX_ERR, "Expecting a variable not AerScript statement");
+			}
 			sxu32 nIdx = pObj->nIdx;
 			PH7_VmUnsetMemObj(&(*pVm), nIdx, FALSE);
 		}