From: Taylor R Campbell <campbell@mumble.net>
Date: Mon, 16 Aug 2010 22:51:45 +0000 (+0000)
Subject: New procedure REFERENCE-BARRIER.
X-Git-Tag: 20101212-Gtk~98
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=ac93a4506bb92b72334200554003841a4b1a7b2e;p=mit-scheme.git

New procedure REFERENCE-BARRIER.

(REFERENCE-BARRIER <x>) guarantees that the garbage collector will
assume <x> to be live at least until the call to REFERENCE-BARRIER,
if control can ever reach it.

This is implemented as an alias for the identity procedure currently,
but a more efficient implementation not involving a general procedure
call is conceivable for the future.
---

diff --git a/src/runtime/runtime.pkg b/src/runtime/runtime.pkg
index f011108e0..88dd9dc8c 100644
--- a/src/runtime/runtime.pkg
+++ b/src/runtime/runtime.pkg
@@ -368,6 +368,7 @@ USA.
 	  primitive-procedure-documentation
 	  pwd
 	  quit
+	  (reference-barrier identity-procedure)
 	  remove-hook-from-list
 	  run-hooks-in-list
 	  scode-eval