Merge from trunk.

diff --cc src/ChangeLog
index 78fa3b501a38083159de162ce373c54811da8c51,2e3142b70150e0208273dfbac346fae32f26e602..ae245a254a0ad60cecf7f42af358564831123509
--- 1/src/ChangeLog
--- 2/src/ChangeLog
+++ b/src/ChangeLog
@@@ -1,16 -1,7 +1,20 @@@
 +2012-04-17  Paul Eggert  <eggert@cs.ucla.edu>
 +
 +      configure: new option --enable-gcc-warnings (Bug#11207)
 +      * Makefile.in (C_WARNINGS_SWITCH): Remove.
 +      (WARN_CFLAGS, WERROR_CFLAGS): New macros.
 +      (ALL_CFLAGS): Use new macros rather than old.
 +      * process.c: Ignore -Wstrict-overflow to work around GCC bug 52904.
 +      * regex.c: Ignore -Wstrict-overflow.  If !emacs, also ignore
 +      -Wunused-but-set-variable, -Wunused-function, -Wunused-macros,
 +      -Wunused-result, -Wunused-variable.  This should go away once
 +      the Emacs and Gnulib regex code is merged.
 +      (xmalloc, xrealloc): Now static.
 +
+ 2012-04-17  Paul Eggert  <eggert@cs.ucla.edu>
+ 
+       * dired.c (Fsystem_groups): Remove unused local.
+ 
  2012-04-17  Glenn Morris  <rgm@gnu.org>
  
        * dired.c (Fsystem_users): Doc fix.