Fix GotoExpr to use VM.currentFunction

SMILEBASIC/VM.d

@@ -927,10 +927,8 @@ class GotoFalse : Code
 }
 class GotoExpr : Code
 {
-    Scope sc;
+    this()
-    this(Scope sc)
     {
-        this.sc = sc;
     }
     override void execute(VM vm)
     {
@@ -939,9 +937,9 @@ class GotoExpr : Code
         if(label.isString)
         {
             int pc;
-            if (sc && sc.func)
+            if (vm.currentFunction)
             {
-                pc = sc.func.label.get(label.castDString, int.min);
+                pc = vm.currentFunction.label.get(label.castDString, int.min);
             }
             else
             {

SMILEBASIC/compiler.d

@@ -1007,7 +1007,7 @@ class Compiler
                     if(!gotou.label)
                     {
                         compileExpression(gotou.labelexpr, s);
-                        genCode(new GotoExpr(s));
+                        genCode(new GotoExpr());
                     }
                     else
                     {