1 files changed, 92 insertions, 27 deletions

diff --git a/m4/longlong.m4 b/m4/longlong.m4
index 3716c09f6..eefb37c45 100644
--- a/m4/longlong.m4
+++ b/m4/longlong.m4
@@ -1,5 +1,5 @@
-# longlong.m4 serial 8
-dnl Copyright (C) 1999-2006 Free Software Foundation, Inc.
+# longlong.m4 serial 17
+dnl Copyright (C) 1999-2007, 2009-2014 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.
@@ -7,42 +7,107 @@ dnl with or without modifications, as long as this notice is preserved.
 dnl From Paul Eggert.
 
 # Define HAVE_LONG_LONG_INT if 'long long int' works.
-# This fixes a bug in Autoconf 2.60, but can be removed once we
-# assume 2.61 everywhere.
+# This fixes a bug in Autoconf 2.61, and can be faster
+# than what's in Autoconf 2.62 through 2.68.
 
 # Note: If the type 'long long int' exists but is only 32 bits large
-# (as on some very old compilers), AC_TYPE_LONG_LONG_INT will not be
+# (as on some very old compilers), HAVE_LONG_LONG_INT will not be
 # defined. In this case you can treat 'long long int' like 'long int'.
 
 AC_DEFUN([AC_TYPE_LONG_LONG_INT],
 [
+  AC_REQUIRE([AC_TYPE_UNSIGNED_LONG_LONG_INT])
   AC_CACHE_CHECK([for long long int], [ac_cv_type_long_long_int],
-    [AC_LINK_IFELSE(
-       [AC_LANG_PROGRAM(
-          [[long long int ll = 9223372036854775807ll;
-            long long int nll = -9223372036854775807LL;
-            typedef int a[((-9223372036854775807LL < 0
-                            && 0 < 9223372036854775807ll)
-                           ? 1 : -1)];
-            int i = 63;]],
-          [[long long int llmax = 9223372036854775807ll;
-            return ((ll << 63) | (ll >> 63) | (ll < i) | (ll > i)
-                    | (llmax / ll) | (llmax % ll));]])],
-       [ac_cv_type_long_long_int=yes],
-       [ac_cv_type_long_long_int=no])])
+     [ac_cv_type_long_long_int=yes
+      if test "x${ac_cv_prog_cc_c99-no}" = xno; then
+        ac_cv_type_long_long_int=$ac_cv_type_unsigned_long_long_int
+        if test $ac_cv_type_long_long_int = yes; then
+          dnl Catch a bug in Tandem NonStop Kernel (OSS) cc -O circa 2004.
+          dnl If cross compiling, assume the bug is not important, since
+          dnl nobody cross compiles for this platform as far as we know.
+          AC_RUN_IFELSE(
+            [AC_LANG_PROGRAM(
+               [[@%:@include <limits.h>
+                 @%:@ifndef LLONG_MAX
+                 @%:@ define HALF \
+                          (1LL << (sizeof (long long int) * CHAR_BIT - 2))
+                 @%:@ define LLONG_MAX (HALF - 1 + HALF)
+                 @%:@endif]],
+               [[long long int n = 1;
+                 int i;
+                 for (i = 0; ; i++)
+                   {
+                     long long int m = n << i;
+                     if (m >> i != n)
+                       return 1;
+                     if (LLONG_MAX / 2 < m)
+                       break;
+                   }
+                 return 0;]])],
+            [],
+            [ac_cv_type_long_long_int=no],
+            [:])
+        fi
+      fi])
   if test $ac_cv_type_long_long_int = yes; then
-    AC_DEFINE([HAVE_LONG_LONG_INT], 1,
-      [Define to 1 if the system has the type `long long int'.])
+    AC_DEFINE([HAVE_LONG_LONG_INT], [1],
+      [Define to 1 if the system has the type 'long long int'.])
   fi
 ])
 
-# This macro is obsolescent and should go away soon.
-AC_DEFUN([gl_AC_TYPE_LONG_LONG],
+# Define HAVE_UNSIGNED_LONG_LONG_INT if 'unsigned long long int' works.
+# This fixes a bug in Autoconf 2.61, and can be faster
+# than what's in Autoconf 2.62 through 2.68.
+
+# Note: If the type 'unsigned long long int' exists but is only 32 bits
+# large (as on some very old compilers), AC_TYPE_UNSIGNED_LONG_LONG_INT
+# will not be defined. In this case you can treat 'unsigned long long int'
+# like 'unsigned long int'.
+
+AC_DEFUN([AC_TYPE_UNSIGNED_LONG_LONG_INT],
 [
-  AC_REQUIRE([AC_TYPE_LONG_LONG_INT])
-  ac_cv_type_long_long=$ac_cv_type_long_long_int
-  if test $ac_cv_type_long_long = yes; then
-    AC_DEFINE(HAVE_LONG_LONG, 1,
-      [Define if you have the 'long long' type.])
+  AC_CACHE_CHECK([for unsigned long long int],
+    [ac_cv_type_unsigned_long_long_int],
+    [ac_cv_type_unsigned_long_long_int=yes
+     if test "x${ac_cv_prog_cc_c99-no}" = xno; then
+       AC_LINK_IFELSE(
+         [_AC_TYPE_LONG_LONG_SNIPPET],
+         [],
+         [ac_cv_type_unsigned_long_long_int=no])
+     fi])
+  if test $ac_cv_type_unsigned_long_long_int = yes; then
+    AC_DEFINE([HAVE_UNSIGNED_LONG_LONG_INT], [1],
+      [Define to 1 if the system has the type 'unsigned long long int'.])
   fi
 ])
+
+# Expands to a C program that can be used to test for simultaneous support
+# of 'long long' and 'unsigned long long'. We don't want to say that
+# 'long long' is available if 'unsigned long long' is not, or vice versa,
+# because too many programs rely on the symmetry between signed and unsigned
+# integer types (excluding 'bool').
+AC_DEFUN([_AC_TYPE_LONG_LONG_SNIPPET],
+[
+  AC_LANG_PROGRAM(
+    [[/* For now, do not test the preprocessor; as of 2007 there are too many
+         implementations with broken preprocessors.  Perhaps this can
+         be revisited in 2012.  In the meantime, code should not expect
+         #if to work with literals wider than 32 bits.  */
+      /* Test literals.  */
+      long long int ll = 9223372036854775807ll;
+      long long int nll = -9223372036854775807LL;
+      unsigned long long int ull = 18446744073709551615ULL;
+      /* Test constant expressions.   */
+      typedef int a[((-9223372036854775807LL < 0 && 0 < 9223372036854775807ll)
+                     ? 1 : -1)];
+      typedef int b[(18446744073709551615ULL <= (unsigned long long int) -1
+                     ? 1 : -1)];
+      int i = 63;]],
+    [[/* Test availability of runtime routines for shift and division.  */
+      long long int llmax = 9223372036854775807ll;
+      unsigned long long int ullmax = 18446744073709551615ull;
+      return ((ll << 63) | (ll >> 63) | (ll < i) | (ll > i)
+              | (llmax / ll) | (llmax % ll)
+              | (ull << 63) | (ull >> 63) | (ull << i) | (ull >> i)
+              | (ullmax / ull) | (ullmax % ull));]])
+])