diff --git a/boot/bootutil/src/bootutil_misc.c b/boot/bootutil/src/bootutil_misc.c
index 87b86350..614c2e07 100644
--- a/boot/bootutil/src/bootutil_misc.c
+++ b/boot/bootutil/src/bootutil_misc.c
@@ -268,7 +268,7 @@ boot_read_enc_key(const struct flash_area *fap, uint8_t slot, struct boot_status
 {
     uint32_t off;
 #if MCUBOOT_SWAP_SAVE_ENCTLV
-    int i;
+    uint32_t i;
 #endif
     int rc;