--- a/m4/ChangeLog
+++ b/m4/ChangeLog
@@ -5,8 +5,11 @@
 
 2005-08-25  Bruno Haible  <bruno@clisp.org>
 
-	* minmax.m4 (gl_MINMAX_IN_HEADER): Add comments.
-	Patch from Stepan Kasal <kasal@ucw.cz>.
+	* minmax.m4: Require autoconf 2.52.
+	(gl_MINMAX_IN_HEADER): Add comments. Use m4_pushdef/m4_popdef instead
+	of define/undefine. Use AS_TR_SH and AS_TR_CPP as more robust
+	alternatives of translit over the alphabet.
+	Based on a patch from Stepan Kasal <kasal@ucw.cz>.
 
 2005-08-24  Paul Eggert  <eggert@cs.ucla.edu>
 

--- a/m4/minmax.m4
+++ b/m4/minmax.m4
@@ -4,6 +4,8 @@
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
+AC_PREREQ(2.52)
+
 AC_DEFUN([gl_MINMAX],
 [
   AC_REQUIRE([gl_PREREQ_MINMAX])
@@ -18,13 +20,12 @@
 
 dnl gl_MINMAX_IN_HEADER(HEADER)
 dnl The parameter has to be a literal header name; it cannot be macro,
-dnl nor a shell variable.
+dnl nor a shell variable. (Because autoheader collects only AC_DEFINE
+dnl invocations with a literal macro name.)
 AC_DEFUN([gl_MINMAX_IN_HEADER],
 [
-  define([header],[translit([$1],[./-],
-                                 [___])])
-  define([HEADER],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
-                                 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
+  m4_pushdef([header], AS_TR_SH([$1]))
+  m4_pushdef([HEADER], AS_TR_CPP([$1]))
   AC_CACHE_CHECK([whether <$1> defines MIN and MAX],
     [gl_cv_minmax_in_]header,
     [AC_TRY_COMPILE([#include <$1>
@@ -35,6 +36,6 @@
     AC_DEFINE([HAVE_MINMAX_IN_]HEADER, 1,
       [Define to 1 if <$1> defines the MIN and MAX macros.])
   fi
-  undefine([HEADER])
-  undefine([header])
+  m4_popdef([HEADER])
+  m4_popdef([header])
 ])