gettimeofday: port recent C++ fix to Emacs

[gnulib.git] / m4 / tzset.m4

diff --git a/m4/tzset.m4 b/m4/tzset.m4
index c3ef373..54af5e0 100644 (file)
--- a/m4/tzset.m4
+++ b/m4/tzset.m4
@@ -1,6 +1,6 @@
-# serial 6
+# serial 7
 
-# Copyright (C) 2003, 2007, 2009-2012 Free Software Foundation, Inc.
+# Copyright (C) 2003, 2007, 2009-2013 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
@@ -20,6 +20,7 @@ AC_DEFUN([gl_FUNC_TZSET], [])
 AC_DEFUN([gl_FUNC_TZSET_CLOBBER],
 [
   AC_REQUIRE([gl_HEADER_SYS_TIME_H])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
   AC_CACHE_CHECK([whether tzset clobbers localtime buffer],
                  gl_cv_func_tzset_clobber,
   [
@@ -47,7 +48,13 @@ main ()
   ]])],
        [gl_cv_func_tzset_clobber=no],
        [gl_cv_func_tzset_clobber=yes],
-       [gl_cv_func_tzset_clobber=yes])])
+       [case "$host_os" in
+                  # Guess all is fine on glibc systems.
+          *-gnu*) gl_cv_func_tzset_clobber="guessing no" ;;
+                  # If we don't know, assume the worst.
+          *)      gl_cv_func_tzset_clobber="guessing yes" ;;
+        esac
+       ])])
 
   AC_DEFINE([HAVE_RUN_TZSET_TEST], [1],
     [Define to 1 if you have run the test for working tzset.])