Default to 'configure --enable-silent-rules'

This greatly shortens the 'make' output, making it more readable
and useful.  For example, on my platform it shortens a
4125-character line "gcc -std=gnu99 -c -Demacs -I. -I. -I../lib
... emacs.c" -- a line so long that it's hard to see what's going
on or where the diagnostics are -- to just "CC emacs.o".
* INSTALL: Document this.
* configure.ac: Add AM_SILENT_RULES([yes]).
(AM_DEFAULT_VERBOSITY): Remove now-unnecessary initialization.
* etc/NEWS: Document this.
Fixes: bug#19501

2 files changed, 9 insertions, 2 deletions

diff --git a/etc/ChangeLog b/etc/ChangeLog
index 7a27312db85..20f88bdecc3 100644
--- a/etc/ChangeLog
+++ b/etc/ChangeLog
@@ -1,3 +1,8 @@
+2015-01-11  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Default to 'configure --enable-silent-rules'
+        * NEWS: Document this.
+
 2015-01-10  Daniel Colascione  <dancol@dancol.org>
 
         * NEWS: Fix typo
diff --git a/etc/NEWS b/etc/NEWS
index 59d90ababc8..b3267e1ce60 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -40,8 +40,10 @@ or by sticking with Emacs 24.4.
 ** The configure option `--with-pkg-config-prog' has been removed.
 Use './configure PKG_CONFIG=/full/name/of/pkg-config' if you need to.
 
-** The configure option '--enable-silent-rules' and the command
-'make V=0' now do a better job of suppressing chatter.
+** The configure option '--enable-silent-rules' is now the default,
+and silent rules are now quieter.  To get the old behavior where
+'make' chatters a lot, configure with '--disable-silent-rules' or
+build with 'make V=1'.
 
 ---
 ** The `grep-changelog' script (and its manual page) are no longer included.