static const char *spi_flash_update_block(struct spi_flash *flash, u32 offset,
                size_t len, const char *buf, char *cmp_buf, size_t *skipped)
 {
-       debug("offset=%#x, sector_size=%#x, len=%#x\n",
+       debug("offset=%#x, sector_size=%#x, len=%#zx\n",
                offset, flash->sector_size, len);
        if (spi_flash_read(flash, offset, len, cmp_buf))
                return "read";
        if (memcmp(cmp_buf, buf, len) == 0) {
-               debug("Skip region %x size %x: no change\n",
+               debug("Skip region %x size %zx: no change\n",
                        offset, len);
                *skipped += len;
                return NULL;