document that forward goto requires quotes

Author: TimToady

S04-control.pod

@@ -13,8 +13,8 @@ Synopsis 4: Blocks and Statements
 
     Created: 19 Aug 2004
 
-    Last Modified: 10 Aug 2011
-    Version: 111
+    Last Modified: 23 Aug 2011
+    Version: 112
 
 This document summarizes Apocalypse 4, which covers the block and
 statement syntax of Perl.
@@ -1232,6 +1232,11 @@ binding (not to mention list generation in the case of C<for>).
 can be emulated for a bare block, so that doesn't fall under the
 prohibition on bypassing formal binding.)
 
+Because it is possible to go to a label that is after the operation,
+and because Perl 6 does one-pass passing, any C<goto> to a label
+that has not been yet declared (or is declared outside the outward
+lexical scope of the C<goto>) must enclose the label in quotes.
+
 =head1 Exceptions
 
 As in Perl 5, many built-in functions simply return an undefined value