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[gnulib.git] / m4 / ulonglong.m4

diff --git a/m4/ulonglong.m4 b/m4/ulonglong.m4
index 15fab9f..9fae98e 100644 (file)
--- a/m4/ulonglong.m4
+++ b/m4/ulonglong.m4
@@ -1,4 +1,4 @@
-# ulonglong.m4 serial 5
+# ulonglong.m4 serial 6
 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 +10,11 @@ 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 '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_CACHE_CHECK([for unsigned long long int],