diff --git a/HISTORY b/HISTORY
index cabf1a2..739009d 100755
--- a/HISTORY
+++ b/HISTORY
@@ -1,3 +1,6 @@
+Jan. 11 2016
+Fixed a crash bug when a DO-UNTIL statement is the end of a program
+
 Jan. 9 2016
 Developing lambda, improved error handling
 Developing lambda, fixed an issue with only a PRINT statement
diff --git a/core/my_basic.c b/core/my_basic.c
index 17ce171..6bb97fe 100755
--- a/core/my_basic.c
+++ b/core/my_basic.c
@@ -11444,7 +11444,8 @@ _loop_begin:
 
 	if(loop_cond_ptr->data.integer) {
 		/* End looping */
-		_skip_to(s, &ast, 0, _DT_EOS);
+		if(ast)
+			_skip_to(s, &ast, 0, _DT_EOS);
 
 		goto _exit;
 	} else {