>From 9e34baba2a6ed10b31de343c25bb28e7ac8f290d Mon Sep 17 00:00:00 2001
From: Bruno Haible <bruno@clisp.org>
Date: Mon, 21 Dec 2020 11:19:05 +0100
Subject: [PATCH 2/6] Port AC_FUNC_GETGROUPS fixes from Gnulib.

* lib/autoconf/functions.m4 (AC_FUNC_GETGROUPS): Improve cross-compilation
guesses.
---
 lib/autoconf/functions.m4 | 79 ++++++++++++++++++++++++++---------------------
 1 file changed, 43 insertions(+), 36 deletions(-)

diff --git a/lib/autoconf/functions.m4 b/lib/autoconf/functions.m4
index a86048f..003e9ce 100644
--- a/lib/autoconf/functions.m4
+++ b/lib/autoconf/functions.m4
@@ -689,44 +689,51 @@ fi
 # When cross-compiling, assume getgroups is broken.
 AN_FUNCTION([getgroups], [AC_FUNC_GETGROUPS])
 AC_DEFUN([AC_FUNC_GETGROUPS],
-[AC_REQUIRE([AC_TYPE_GETGROUPS])dnl
-AC_REQUIRE([AC_TYPE_SIZE_T])dnl
-AC_REQUIRE([AC_CANONICAL_HOST])dnl for cross-compiles
-AC_CHECK_FUNC(getgroups)
+[
+  AC_REQUIRE([AC_TYPE_GETGROUPS])dnl
+  AC_REQUIRE([AC_TYPE_SIZE_T])dnl
+  AC_REQUIRE([AC_CANONICAL_HOST])dnl for cross-compiles
+  AC_CHECK_FUNC([getgroups])
 
-# If we don't yet have getgroups, see if it's in -lbsd.
-# This is reported to be necessary on an ITOS 3000WS running SEIUX 3.1.
-ac_save_LIBS=$LIBS
-if test $ac_cv_func_getgroups = no; then
-  AC_CHECK_LIB(bsd, getgroups, [GETGROUPS_LIB=-lbsd])
-fi
+  # If we don't yet have getgroups, see if it's in -lbsd.
+  # This is reported to be necessary on an ITOS 3000WS running SEIUX 3.1.
+  ac_save_LIBS=$LIBS
+  if test $ac_cv_func_getgroups = no; then
+    AC_CHECK_LIB(bsd, getgroups, [GETGROUPS_LIB=-lbsd])
+  fi
 
-# Run the program to test the functionality of the system-supplied
-# getgroups function only if there is such a function.
-if test $ac_cv_func_getgroups = yes; then
-  AC_CACHE_CHECK([for working getgroups], ac_cv_func_getgroups_works,
-   [AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
-      [[/* On Ultrix 4.3, getgroups (0, 0) always fails.  */
-       return getgroups (0, 0) == -1;]])],
-		  [ac_cv_func_getgroups_works=yes],
-		  [ac_cv_func_getgroups_works=no],
-		  [case "$host_os" in # ((
-			     # Guess yes on glibc systems.
-		     *-gnu*) ac_cv_func_getgroups_works="guessing yes" ;;
-			     # If we don't know, assume the worst.
-		     *)      ac_cv_func_getgroups_works="guessing no" ;;
-		   esac])
-   ])
-else
-  ac_cv_func_getgroups_works=no
-fi
-case "$ac_cv_func_getgroups_works" in
-  *yes)
-    AC_DEFINE(HAVE_GETGROUPS, 1,
-	      [Define to 1 if your system has a working `getgroups' function.])
-    ;;
-esac
-LIBS=$ac_save_LIBS
+  # Run the program to test the functionality of the system-supplied
+  # getgroups function only if there is such a function.
+  if test $ac_cv_func_getgroups = yes; then
+    AC_CACHE_CHECK([for working getgroups], [ac_cv_func_getgroups_works],
+      [AC_RUN_IFELSE(
+         [AC_LANG_PROGRAM(
+            [AC_INCLUDES_DEFAULT],
+            [[/* On NeXTstep 3.2, getgroups (0, 0) always fails.  */
+              return getgroups (0, 0) == -1;]])
+         ],
+         [ac_cv_func_getgroups_works=yes],
+         [ac_cv_func_getgroups_works=no],
+         [case "$host_os" in # ((
+                           # Guess yes on glibc systems.
+            *-gnu* | gnu*) ac_cv_func_getgroups_works="guessing yes" ;;
+                           # Guess yes on musl systems.
+            *-musl*)       ac_cv_func_getgroups_works="guessing yes" ;;
+                           # If we don't know, assume the worst.
+            *)             ac_cv_func_getgroups_works="guessing no" ;;
+          esac
+         ])
+      ])
+  else
+    ac_cv_func_getgroups_works=no
+  fi
+  case "$ac_cv_func_getgroups_works" in
+    *yes)
+      AC_DEFINE([HAVE_GETGROUPS], [1],
+        [Define to 1 if your system has a working `getgroups' function.])
+      ;;
+  esac
+  LIBS=$ac_save_LIBS
 ])# AC_FUNC_GETGROUPS
 
 
-- 
2.7.4