diff --git a/examples/mifare-classic-format.c b/examples/mifare-classic-format.c
index 5f6d46b..2779b47 100644
--- a/examples/mifare-classic-format.c
+++ b/examples/mifare-classic-format.c
@@ -83,7 +83,7 @@ main(int argc, char *argv[])
 
 	for (size_t n = 0; n < sector_count; n++) {
 	    if (try_format_sector (*tag, n) < 0) {
-		warnx ("%s: Can't format sector %d (0x%02x)", tag_uid,  n, n);
+		warnx ("%s: Can't format sector %ld (0x%02lx)", tag_uid,  n, n);
 		error = 1;
 	    }
 	}
diff --git a/test/mifare_classic_fixture.c b/test/mifare_classic_fixture.c
index 0158cea..9dbfe52 100644
--- a/test/mifare_classic_fixture.c
+++ b/test/mifare_classic_fixture.c
@@ -11,12 +11,12 @@ setup ()
     int res;
 
     device = nfc_connect (NULL);
-    cut_assert_not_null (device, "No device found");
+    cut_assert_not_null (device, cut_message ("No device found"));
 
     tags = mifare_classic_get_tags (device);
-    cut_assert_not_null (tags ,"Error enumerating NFC tags");
+    cut_assert_not_null (tags, cut_message ("Error enumerating NFC tags"));
 
-    cut_assert_not_null (tags[0], "No MIFARE CLassic tag on NFC device");
+    cut_assert_not_null (tags[0], cut_message ("No MIFARE CLassic tag on NFC device"));
 
     tag = tags[0];
 
diff --git a/test/test_mifare_classic.c b/test/test_mifare_classic.c
index aeaeb1a..6c52ef8 100644
--- a/test/test_mifare_classic.c
+++ b/test/test_mifare_classic.c
@@ -103,7 +103,7 @@ void
 test_mifare_classic_read_mad (void)
 {
     Mad mad = mad_read (tag);
-    cut_assert_not_null (tag);
+    cut_assert_not_null (mad);
 }
 
 void
@@ -169,7 +169,7 @@ test_mifare_classic_value_block_increment (void)
     int32_t value;
     MifareClassicBlockNumber adr;
     res = mifare_classic_read_value (tag, block, &value, &adr);
-    cut_assert_equal_int (0, res, 0);
+    cut_assert_equal_int (0, res);
     cut_assert_equal_int (1000, value);
     cut_assert_equal_int (0x00, adr);