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[pspp] / m4 / longlong.m4

diff --git a/m4/longlong.m4 b/m4/longlong.m4
index ea7c485c368e84847d4e1b076c9ea16e3f8b60e3..3716c09f6caf562c8b70eb0c8ff498f3e210c6b7 100644 (file)
--- a/m4/longlong.m4
+++ b/m4/longlong.m4
@@ -1,4 +1,4 @@
-# longlong.m4 serial 6
+# longlong.m4 serial 8
 dnl Copyright (C) 1999-2006 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -10,6 +10,10 @@ dnl From Paul Eggert.
 # This fixes a bug in Autoconf 2.60, but can be removed once we
 # assume 2.61 everywhere.
 
+# 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
+# defined. In this case you can treat 'long long int' like 'long int'.
+
 AC_DEFUN([AC_TYPE_LONG_LONG_INT],
 [
   AC_CACHE_CHECK([for long long int], [ac_cv_type_long_long_int],
@@ -22,8 +26,8 @@ AC_DEFUN([AC_TYPE_LONG_LONG_INT],
                           ? 1 : -1)];
            int i = 63;]],
          [[long long int llmax = 9223372036854775807ll;
-           return (ll << 63 | ll >> 63 | ll < i | ll > i
-                   | llmax / ll | llmax % ll);]])],
+           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])])
   if test $ac_cv_type_long_long_int = yes; then