diff --git a/src/device/cartridge.c b/src/device/cartridge.c
index 00464026a..cb3c5e412 100644
--- a/src/device/cartridge.c
+++ b/src/device/cartridge.c
@@ -92,8 +92,8 @@ cart_image_close(int drive)
 static void
 cart_image_load(int drive, char *fn)
 {
-    FILE    *fp;
-    uint32_t size;
+    FILE    *fp   = NULL;
+    uint32_t size = 0;
     uint32_t base = 0x00000000;
 
     cart_image_close(drive);
@@ -137,7 +137,7 @@ cart_image_load(int drive, char *fn)
 static void
 cart_load_common(int drive, char *fn, uint8_t hard_reset)
 {
-    FILE *fp;
+    FILE *fp = NULL;
 
     cartridge_log("Cartridge: loading drive %d with '%s'\n", drive, fn);