mutt: Add idn to MUTTLIBS instead of LIBS (see #3638)

[Brendan Cully]

changeset: 6482:c0180991c352
user:      Kevin McCarthy <ke...@8t8.us>
date:      Mon Aug 17 14:51:07 2015 -0700
link:      http://dev.mutt.org/hg/mutt/rev/c0180991c352

Add idn to MUTTLIBS instead of LIBS (see #3638)

Currently, -lidn is included while linking all the mutt binaries.  Add
it to MUTTLIBS instead so it's only used for the mutt linking.

Also, add $LIBICONV to $LIBS before checking for some of the idna
functions.  On some sytems, there are apparently issues when using
static linking. (Thanks to grarpamp for reporting).

diffs (26 lines):

diff -r 356443232291 -r c0180991c352 configure.ac
--- a/configure.ac      Mon Aug 17 12:31:40 2015 -0700
+++ b/configure.ac      Mon Aug 17 14:51:07 2015 -0700
@@ -1191,14 +1191,22 @@
                      have_idna_h=yes
                      break])
 
+    mutt_save_LIBS="$LIBS"
+    LIBS=
+
     AC_SEARCH_LIBS([stringprep_check_version], [idn], [
       AC_DEFINE([HAVE_LIBIDN], 1, [Define to 1 if you have the GNU idn 
library])
       MUTT_LIB_OBJECTS="$MUTT_LIB_OBJECTS mutt_idna.o"
+      MUTTLIBS="$MUTTLIBS $LIBS"
+
+      LIBS="$LIBS $LIBICONV"
       AC_CHECK_FUNCS(idna_to_unicode_utf8_from_utf8 idna_to_unicode_8z8z)
       AC_CHECK_FUNCS(idna_to_ascii_from_utf8 idna_to_ascii_8z)
       AC_CHECK_FUNCS(idna_to_ascii_lz idna_to_ascii_from_locale)
     ])
 
+    LIBS="$mutt_save_LIBS"
+
     if test "$with_idn" != auto; then
       if test $have_stringprep_h = no || test $have_idna_h = no || test 
$ac_cv_search_stringprep_check_version = no; then
        AC_MSG_ERROR([IDN was requested, but libidn was not usable on this 
system])