--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2010-11-27  Bruno Haible  <bruno@clisp.org>
+
+	readline: Improve configure output.
+	* m4/readline.m4 (gl_FUNC_READLINE): Make the
+	"checking for readline..." result understandable.
+
 2010-11-27  Bruno Haible  <bruno@clisp.org>
 
 	*printf-posix: Detect a bug on Solaris 10/x86.

--- a/m4/readline.m4
+++ b/m4/readline.m4
@@ -1,4 +1,4 @@
-# readline.m4 serial 7
+# readline.m4 serial 8
 dnl Copyright (C) 2005, 2006, 2009, 2010 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -40,7 +40,12 @@
       AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>
 #include <readline/readline.h>]],
           [[readline((char*)0);]])],
-        [gl_cv_lib_readline=" -l$extra_lib"])
+        [if test -n "$extra_lib"; then
+           gl_cv_lib_readline="yes, requires -l$extra_lib"
+         else
+           gl_cv_lib_readline="yes"
+         fi
+        ])
       if test "$gl_cv_lib_readline" != no; then
         break
       fi
@@ -50,9 +55,10 @@
 
   if test "$gl_cv_lib_readline" != no; then
     AC_DEFINE([HAVE_READLINE], [1], [Define if you have the readline library.])
-    if test "$gl_cv_lib_readline" != " -l"; then
-      LIBREADLINE="$LIBREADLINE$gl_cv_lib_readline"
-      LTLIBREADLINE="$LTLIBREADLINE$gl_cv_lib_readline"
+    extra_lib=`echo "$gl_cv_lib_readline" | sed -n -e 's/yes, requires //p'`
+    if test -n "$extra_lib"; then
+      LIBREADLINE="$LIBREADLINE $extra_lib"
+      LTLIBREADLINE="$LTLIBREADLINE $extra_lib"
     fi
     AC_MSG_CHECKING([how to link with libreadline])
     AC_MSG_RESULT([$LIBREADLINE])
@@ -68,7 +74,7 @@
 
   AC_CHECK_HEADERS([readline/readline.h])
 
-  if test $gl_cv_lib_readline = no; then
+  if test "$gl_cv_lib_readline" = no; then
     AC_LIBOBJ([readline])
     gl_PREREQ_READLINE
   fi