diff --git a/setter/src/macos/attr.c b/setter/src/macos/attr.c
index ed433a4..73cd58d 100644
--- a/setter/src/macos/attr.c
+++ b/setter/src/macos/attr.c
@@ -83,7 +83,7 @@ void FileAttributes(const char* path)
     for(i = 0; i < KNOWN_MAC_ATTRS; i++)
     {
         memset(str255, 0, 256);
-        memcpy(str255, mac_attrs[i].filename, strlen(mac_attrs[i].filename));
+        memcpy(str255, mac_attrs[i].filename, strlen((const char*)mac_attrs[i].filename));
 
         memset(&finderInfo, 0, sizeof(FInfo));
         rc = HCreate(refNum, dirId, str255, ostUnknown, ftGenericDocumentPC);
diff --git a/setter/src/macos/attr.h b/setter/src/macos/attr.h
index a7011f5..8f2a52e 100644
--- a/setter/src/macos/attr.h
+++ b/setter/src/macos/attr.h
@@ -33,13 +33,13 @@ Copyright (C) 2011-2021 Natalia Portillo
 
 typedef struct
 {
-    char*    filename;
-    char     contents[170];
-    char     description[63];
-    uint16_t flags;
-    OSType   type;
-    OSType   creator;
-    Point    location;
+    unsigned char* filename;
+    char           contents[170];
+    char           description[63];
+    uint16_t       flags;
+    OSType         type;
+    OSType         creator;
+    Point          location;
 } mac_attr_tests_t;
 
 #define KNOWN_MAC_ATTRS 33