gettext: Recognize a statically built libintl on macOS and AIX

[Bruno Haible]

This patch fixes a failure of the "checking for GNU gettext in libintl..." test
to recognize a libintl built with --disable-shared. It's a long-standing bug
(certainly 10 years or older). It was not noticed because hardly anyone builds
with --disable-shared nowadays. Only the GCC people have a habit of doing so.


2023-11-17  Bruno Haible  <bruno@clisp.org>

        gettext: Recognize a statically built libintl on macOS and AIX.
        Reported by David Edelsohn <dje.gcc@gmail.com> in
        <https://gcc.gnu.org/pipermail/gcc-patches/2023-November/636558.html>.
        * m4/gettext.m4 (AM_GNU_GETTEXT): In the
        "checking for GNU gettext in libintl..." test, add also the special
        system library dependencies needed on macOS and AIX.

diff --git a/m4/gettext.m4 b/m4/gettext.m4
index 019d1adb5a..16f9db1879 100644
--- a/m4/gettext.m4
+++ b/m4/gettext.m4
@@ -1,4 +1,4 @@
-# gettext.m4 serial 77 (gettext-0.22)
+# gettext.m4 serial 78 (gettext-0.22.4)
 dnl Copyright (C) 1995-2014, 2016, 2018-2023 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -210,9 +210,16 @@ AC_DEFUN([AM_GNU_GETTEXT]
                  ]])],
               [eval "$gt_func_gnugettext_libintl=yes"],
               [eval "$gt_func_gnugettext_libintl=no"])
-            dnl Now see whether libintl exists and depends on libiconv.
-            if { eval "gt_val=\$$gt_func_gnugettext_libintl"; test "$gt_val" 
!= yes; } && test -n "$LIBICONV"; then
-              LIBS="$LIBS $LIBICONV"
+            dnl Now see whether libintl exists and depends on libiconv or other
+            dnl OS dependent libraries, specifically on macOS and AIX.
+            gt_LIBINTL_EXTRA="$INTL_MACOSX_LIBS"
+            AC_REQUIRE([AC_CANONICAL_HOST])
+            case "$host_os" in
+              aix*) gt_LIBINTL_EXTRA="-lpthread" ;;
+            esac
+            if { eval "gt_val=\$$gt_func_gnugettext_libintl"; test "$gt_val" 
!= yes; } \
+               && { test -n "$LIBICONV" || test -n "$gt_LIBINTL_EXTRA"; }; then
+              LIBS="$LIBS $LIBICONV $gt_LIBINTL_EXTRA"
               AC_LINK_IFELSE(
                 [AC_LANG_PROGRAM(
                    [[
@@ -234,8 +241,8 @@ AC_DEFUN([AM_GNU_GETTEXT]
 bindtextdomain ("", "");
 return * gettext ("")$gt_expression_test_code + __GNU_GETTEXT_SYMBOL_EXPRESSION
                    ]])],
-                [LIBINTL="$LIBINTL $LIBICONV"
-                 LTLIBINTL="$LTLIBINTL $LTLIBICONV"
+                [LIBINTL="$LIBINTL $LIBICONV $gt_LIBINTL_EXTRA"
+                 LTLIBINTL="$LTLIBINTL $LTLIBICONV $gt_LIBINTL_EXTRA"
                  eval "$gt_func_gnugettext_libintl=yes"
                 ])
             fi