[src/trunk]: src/usr.bin/make make: fix documentation of Lst_MoveAll

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c75f2dcf846a
branches:  trunk
changeset: 1019608:c75f2dcf846a
user:      rillig <rillig%NetBSD.org@localhost>
date:      Mon Mar 15 16:45:30 2021 +0000

description:
make: fix documentation of Lst_MoveAll

In CLEANUP mode, was originally meant to track memory allocations but is
useful during debugging as well, initialize the list.  There is no
distinct constant representing an invalid pointer, otherwise that would
have been an even better choice.

diffstat:

 usr.bin/make/lst.c |  10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diffs (38 lines):

diff -r 0f9c8e12b3a1 -r c75f2dcf846a usr.bin/make/lst.c
--- a/usr.bin/make/lst.c        Mon Mar 15 16:06:05 2021 +0000
+++ b/usr.bin/make/lst.c        Mon Mar 15 16:45:30 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: lst.c,v 1.104 2021/02/01 19:39:31 rillig Exp $ */
+/* $NetBSD: lst.c,v 1.105 2021/03/15 16:45:30 rillig Exp $ */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -34,7 +34,7 @@
 
 #include "make.h"
 
-MAKE_RCSID("$NetBSD: lst.c,v 1.104 2021/02/01 19:39:31 rillig Exp $");
+MAKE_RCSID("$NetBSD: lst.c,v 1.105 2021/03/15 16:45:30 rillig Exp $");
 
 static ListNode *
 LstNodeNew(ListNode *prev, ListNode *next, void *datum)
@@ -205,7 +205,7 @@
 
 /*
  * Move all nodes from src to the end of dst.
- * The source list becomes empty but is not freed.
+ * The source list becomes indeterminate.
  */
 void
 Lst_MoveAll(List *dst, List *src)
@@ -219,6 +219,10 @@
 
                dst->last = src->last;
        }
+#ifdef CLEANUP
+       src->first = NULL;
+       src->last = NULL;
+#endif
 }
 
 /* Copy the element data from src to the start of dst. */