diff --git a/flashrom.c b/flashrom.c
index cb1dca6..06b1854 100644
--- a/flashrom.c
+++ b/flashrom.c
@@ -1253,7 +1253,7 @@
 		ret = 1;
 		goto out;
 	}
-	if (image_stat.st_size != size) {
+	if (image_stat.st_size != (intmax_t)size) {
 		msg_gerr("Error: Image size (%jd B) doesn't match the flash chip's size (%lu B)!\n",
 			 (intmax_t)image_stat.st_size, size);
 		ret = 1;