From c13c43a111e825bb87a465ccbb9533f302beaa09 Mon Sep 17 00:00:00 2001
From: simonmar <unknown>
Date: Fri, 10 Sep 1999 11:11:52 +0000
Subject: [PATCH] [project @ 1999-09-10 11:11:51 by simonmar] Fix run queue
 corruption bug, introduced in recent threadWait commit.

This fixes the "memo002 goes off into outer space" bug.
---
 ghc/rts/Schedule.c |    3 ++-
 ghc/rts/Schedule.h |    5 ++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/ghc/rts/Schedule.c b/ghc/rts/Schedule.c
index 8450d97..30381a4 100644
--- a/ghc/rts/Schedule.c
+++ b/ghc/rts/Schedule.c
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
- * $Id: Schedule.c,v 1.24 1999/08/25 16:11:51 simonmar Exp $
+ * $Id: Schedule.c,v 1.25 1999/09/10 11:11:51 simonmar Exp $
  *
  * (c) The GHC Team, 1998-1999
  *
@@ -654,6 +654,7 @@ StgTSO *unblockOne(StgTSO *tso)
   ASSERT(tso->why_blocked != NotBlocked);
   tso->why_blocked = NotBlocked;
   next = tso->link;
+  tso->link = END_TSO_QUEUE;
   PUSH_ON_RUN_QUEUE(tso);
   IF_DEBUG(scheduler,belch("Waking up thread %ld", tso->id));
   return next;
diff --git a/ghc/rts/Schedule.h b/ghc/rts/Schedule.h
index 4a2cac0..3bc46d5 100644
--- a/ghc/rts/Schedule.h
+++ b/ghc/rts/Schedule.h
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
- * $Id: Schedule.h,v 1.6 1999/08/25 16:11:51 simonmar Exp $
+ * $Id: Schedule.h,v 1.7 1999/09/10 11:11:52 simonmar Exp $
  *
  * (c) The GHC Team 1998-1999
  *
@@ -43,6 +43,9 @@ extern StgTSO *MainTSO; /* temporary hack */
 #endif
 #define END_TSO_QUEUE  ((StgTSO *)(void*)&END_TSO_QUEUE_closure)
 
+/* Add a thread to the end of the run queue.
+ * NOTE: tso->link should be END_TSO_QUEUE before calling this macro.
+ */
 #define PUSH_ON_RUN_QUEUE(tso)			\
     if (run_queue_hd == END_TSO_QUEUE) {        \
       run_queue_hd = tso;			\
-- 
1.7.10.4