X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fullong_max.m4;h=61fdce25e28fbd7aaa2bf58cd2b16600e0c18407;hb=e3ad62845a3b14a8a6aac9e966cdf0642e9294fe;hp=49fc3402d4d9706117c2b53afe123b6f8821b304;hpb=2d47f3cd1e2b6ac70efda6a868d97bed866e9d6f;p=gnulib.git

diff --git a/m4/ullong_max.m4 b/m4/ullong_max.m4
index 49fc3402d..61fdce25e 100644
--- a/m4/ullong_max.m4
+++ b/m4/ullong_max.m4
@@ -11,36 +11,17 @@ AC_DEFUN([gl_ULLONG_MAX],
 [
   dnl Avoid _AC_COMPUTE_INT-related macros, as they may not work with
   dnl types wider than long int, due to problems with expr.
-  AC_CACHE_CHECK([for ULLONG_MAX], gl_cv_ullong_max,
-    [gl_cv_ullong_max=no
-     AC_EGREP_CPP([ULLONG_MAX is defined],
-       [
-	#include <limits.h>
-	#ifdef ULLONG_MAX
-	 "ULLONG_MAX is defined"
-	#endif
-       ],
-       [gl_cv_ullong_max=yes])
-     case $gl_cv_ullong_max in
-     no)
-       for gl_expr in \
-	 18446744073709551615ULL \
-	 4722366482869645213695ULL \
-	 340282366920938463463374607431768211455ULL
-       do
-	 AC_TRY_COMPILE([],
-	   [char test[$gl_expr == (unsigned long long int) -1 ? 1 : -1];
-	    static unsigned long long int i = $gl_expr;
-	    return i && test;],
-	   [gl_cv_ullong_max=$gl_expr])
-         test $gl_cv_ullong_max != no && break
-       done
-     esac])
-  case $gl_cv_ullong_max in
-  yes | no) ;;
-  *)
-    AC_DEFINE_UNQUOTED([ULLONG_MAX], [$gl_cv_ullong_max],
-      [Define as the maximum value of the type 'unsigned long long int',
-       if the system doesn't define it, and if the system has that type.]);;
-  esac
+  AC_CACHE_CHECK([whether ULONG_MAX < ULLONG_MAX],
+    [gl_cv_ulong_max_lt_ullong_max],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_BOOL_COMPILE_TRY(
+	 [AC_INCLUDES_DEFAULT],
+	 [[(unsigned long int) -1 < (unsigned long long int) -1]])],
+      [gl_cv_ulong_max_lt_ullong_max=yes],
+      [gl_cv_ulong_max_lt_ullong_max=no])])
+  if test $gl_cv_ulong_max_lt_ullong_max = yes; then
+    AC_DEFINE([ULONG_MAX_LT_ULLONG_MAX], 1,
+      [Define if ULONG_MAX < ULLONG_MAX, even if your compiler does not
+       support ULLONG_MAX.])
+  fi
 ])