X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Ftime_r.m4;h=9bb28005fc0021f834ce64a17d5ded2de013608d;hb=279067b9021cfd0935711cae3f3297ae4b3808af;hp=8146f085c984c5e1ef635560e4098cad1cc6ceba;hpb=e3f4b8adddfc8fc9f7dc9e07852eaacec5297d5d;p=gnulib.git

diff --git a/m4/time_r.m4 b/m4/time_r.m4
index 8146f085c..9bb28005f 100644
--- a/m4/time_r.m4
+++ b/m4/time_r.m4
@@ -1,6 +1,6 @@
-dnl Reentrant time functions like localtime_r.
+dnl Reentrant time functions: localtime_r, gmtime_r.
 
-dnl Copyright (C) 2003, 2006 Free Software Foundation, Inc.
+dnl Copyright (C) 2003, 2006-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -9,25 +9,48 @@ dnl Written by Paul Eggert.
 
 AC_DEFUN([gl_TIME_R],
 [
-  AC_LIBSOURCES([time_r.c, time_r.h])
+  dnl Persuade glibc and Solaris <time.h> to declare localtime_r.
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
-  AC_REQUIRE([gl_C_RESTRICT])
 
-  AC_CACHE_CHECK([whether localtime_r is compatible with its POSIX signature],
-    [gl_cv_time_r_posix],
-    [AC_TRY_COMPILE(
-       [#include <time.h>],
-       [/* We don't need to append 'restrict's to the argument types,
-	   even though the POSIX signature has the 'restrict's,
-	   since C99 says they can't affect type compatibility.  */
-	struct tm * (*ptr) (time_t const *, struct tm *) = localtime_r;],
-       [gl_cv_time_r_posix=yes],
-       [gl_cv_time_r_posix=no])])
-  if test $gl_cv_time_r_posix = yes; then
-    AC_DEFINE([HAVE_TIME_R_POSIX], 1,
-      [Define to 1 if localtime_r, etc. have the type signatures that
-       POSIX requires.])
+  AC_REQUIRE([gl_HEADER_TIME_H_DEFAULTS])
+  AC_REQUIRE([AC_C_RESTRICT])
+
+  dnl Some systems don't declare localtime_r() and gmtime_r() if _REENTRANT is
+  dnl not defined.
+  AC_CHECK_DECLS_ONCE([localtime_r])
+  if test $ac_cv_have_decl_localtime_r = no; then
+    HAVE_DECL_LOCALTIME_R=0
+  fi
+
+  AC_CHECK_FUNCS_ONCE([localtime_r])
+  if test $ac_cv_func_localtime_r = yes; then
+    HAVE_LOCALTIME_R=1
+    AC_CACHE_CHECK([whether localtime_r is compatible with its POSIX signature],
+      [gl_cv_time_r_posix],
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[#include <time.h>]],
+            [[/* We don't need to append 'restrict's to the argument types,
+                 even though the POSIX signature has the 'restrict's,
+                 since C99 says they can't affect type compatibility.  */
+              struct tm * (*ptr) (time_t const *, struct tm *) = localtime_r;
+              if (ptr) return 0;
+              /* Check the return type is a pointer.
+                 On HP-UX 10 it is 'int'.  */
+              *localtime_r (0, 0);]])
+         ],
+         [gl_cv_time_r_posix=yes],
+         [gl_cv_time_r_posix=no])
+      ])
+    if test $gl_cv_time_r_posix = yes; then
+      REPLACE_LOCALTIME_R=0
+    else
+      REPLACE_LOCALTIME_R=1
+    fi
   else
+    HAVE_LOCALTIME_R=0
+  fi
+  if test $HAVE_LOCALTIME_R = 0 || test $REPLACE_LOCALTIME_R = 1; then
     AC_LIBOBJ([time_r])
     gl_PREREQ_TIME_R
   fi