diff --git a/ChangeLog b/ChangeLog
index 43b2906a8..3144dd0fe 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2013-04-27  Paulo Flabiano Smorigo <pfsmorigo@br.ibm.com>
+
+	* include/grub/macho.h: Set GRUB_MACHO_FAT_EFI_MAGIC as unsigned.
+
 2013-04-27  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/term/ns8250.c: Systematically probe ports by writing
diff --git a/include/grub/macho.h b/include/grub/macho.h
index 18434ff8e..2bfc30f1a 100644
--- a/include/grub/macho.h
+++ b/include/grub/macho.h
@@ -34,7 +34,7 @@ enum
   };
 
 #define GRUB_MACHO_FAT_MAGIC 0xcafebabe
-#define GRUB_MACHO_FAT_EFI_MAGIC 0x0ef1fab9
+#define GRUB_MACHO_FAT_EFI_MAGIC 0x0ef1fab9U
 
 typedef grub_uint32_t grub_macho_cpu_type_t;
 typedef grub_uint32_t grub_macho_cpu_subtype_t;