diff --git a/aclocal.m4 b/aclocal.m4
index e5b7dbf..01cecf1 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -73,6 +73,7 @@ AC_DEFUN([OD_OBJC_RUNTIME],[
 				AC_LANG_PROGRAM([
 						#include <objc/objc.h>
 						#include <objc/Object.h>
+						#include <stdio.h>
 					], [
 						Object *obj = @<:@Object alloc@:>@;
 						puts(@<:@obj name@:>@);
@@ -94,6 +95,7 @@ AC_DEFUN([OD_OBJC_RUNTIME],[
 					AC_LANG_PROGRAM([
 							#include <objc/objc.h>
 							#include <objc/Object.h>
+							#include <stdio.h>
 						], [
 							Object *obj = @<:@Object alloc@:>@;
 							puts(@<:@obj name@:>@);
@@ -131,6 +133,7 @@ AC_DEFUN([OD_OBJC_RUNTIME],[
 					AC_LANG_PROGRAM([
 							#include <objc/objc.h>
 							#include <objc/objc-api.h>
+							#include <stdio.h>
 						], [
 							id class = objc_lookUpClass("Object");
 							id obj = @<:@class alloc@:>@;
@@ -162,6 +165,7 @@ AC_DEFUN([OD_OBJC_RUNTIME],[
 							#else
 							#include <objc/objc-api.h>
 							#endif
+							#include <stdio.h>
 						], [
 							#ifdef __GNU_LIBOBJC_
 							Class class = objc_lookUpClass("Object");