--- a/m4/xstrtoumax.m4
+++ b/m4/xstrtoumax.m4
@@ -1,15 +1,15 @@
-#serial 5
-dnl Closely related to xstrtoimax.m4.  Keep these files in sync.
+#serial 3
 
 # autoconf tests required for use of xstrtoumax.c
 
 AC_DEFUN([jm_AC_PREREQ_XSTRTOUMAX],
 [
+  AC_REQUIRE([jm_AC_TYPE_INTMAX_T])
   AC_REQUIRE([jm_AC_TYPE_UINTMAX_T])
-  AC_REQUIRE([jm_AC_HEADER_INTTYPES_H])
+  AC_REQUIRE([jm_AC_TYPE_LONG_LONG])
   AC_REQUIRE([jm_AC_TYPE_UNSIGNED_LONG_LONG])
   AC_CHECK_DECLS([strtoul, strtoull])
-  AC_CHECK_HEADERS(limits.h stdlib.h)
+  AC_CHECK_HEADERS(limits.h stdlib.h inttypes.h)
 
   AC_CACHE_CHECK([whether <inttypes.h> defines strtoumax as a macro],
     jm_cv_func_strtoumax_macro,
@@ -24,27 +24,17 @@
     AC_REPLACE_FUNCS(strtoumax)
   fi
 
-  dnl We don't need (and can't compile) the replacement strtoull
-  dnl unless the type `unsigned long long' exists.
-  dnl Also, only the replacement strtoumax invokes strtoull,
-  dnl so we need the replacement strtoull only if strtoumax does not exist.
-  case "$ac_cv_type_unsigned_long_long,$jm_cv_func_strtoumax_macro,$ac_cv_func_strtoumax" in
-    yes,no,no)
-      AC_REPLACE_FUNCS(strtoull)
-
-      dnl Check for strtol.  Mainly as a cue to cause automake to include
-      dnl strtol.c -- that file is included by each of strtoul.c and strtoull.c.
-      AC_REPLACE_FUNCS(strtol)
-      ;;
-  esac
-
+  dnl Only the replacement strtoumax invokes strtoul and strtoull,
+  dnl so we need the replacements only if strtoumax does not exist.
   case "$jm_cv_func_strtoumax_macro,$ac_cv_func_strtoumax" in
     no,no)
       AC_REPLACE_FUNCS(strtoul)
 
-      dnl See explanation above.
-      AC_REPLACE_FUNCS(strtol)
+      dnl We don't need (and can't compile) the replacement strtoull
+      dnl unless the type `unsigned long long' exists.
+      if test "$ac_cv_type_unsigned_long_long" = yes; then
+	AC_REPLACE_FUNCS(strtoull)
+      fi
       ;;
   esac
-
 ])