svn commit: r227769 - head

[Glen Barber]

Author: gjb (doc committer)
Date: Sun Nov 20 19:05:32 2011
New Revision: 227769
URL: http://svn.freebsd.org/changeset/base/227769

Log:
  Add a note to src/Makefile that explains that 'rm' runs twice because the
  second invocation only needs to operate on files with the immutable flag
  set.
  
  Submitted by:		arundel (via private email) (original version)
  Discussed on:		-toolchain@
  MFC after:		3 days

Modified:
  head/Makefile

Modified: head/Makefile
==============================================================================
--- head/Makefile	Sun Nov 20 18:01:45 2011	(r227768)
+++ head/Makefile	Sun Nov 20 19:05:32 2011	(r227769)
@@ -185,7 +185,10 @@ buildworld: upgrade_checks
 # files with chflags set, so this unsets them and tries the 'rm' a
 # second time.  There are situations where this target will be cleaning
 # some directories via more than one method, but that duplication is
-# needed to correctly handle all the possible situations.
+# needed to correctly handle all the possible situations.  Removing all
+# files without the immutable flag set in the first 'rm' instance saves
+# time, because 'chflags' will need to operate on fewer files (with the
+# immutable flag set) afterwards.
 #
 BW_CANONICALOBJDIR:=${MAKEOBJDIRPREFIX}${.CURDIR}
 cleanworld: