Index: uspace/lib/block/libblock.c
===================================================================
--- uspace/lib/block/libblock.c	(revision 991f645937e5e281d6996ad4623f9ab33c71916d)
+++ uspace/lib/block/libblock.c	(revision 052f5356b69e847883225359c2733803793fc083)
@@ -816,6 +816,6 @@
 	    UPPER32(ba), cnt);
 	if (rc != EOK) {
-		printf("Error %d reading %d blocks starting at block %" PRIuOFF64
-		    " from device handle %d\n", rc, cnt, ba,
+		printf("Error %d reading %zu blocks starting at block %" PRIuOFF64
+		    " from device handle %" PRIun "\n", rc, cnt, ba,
 		    devcon->devmap_handle);
 #ifndef NDEBUG
@@ -843,6 +843,6 @@
 	    UPPER32(ba), cnt);
 	if (rc != EOK) {
-		printf("Error %d writing %d blocks starting at block %" PRIuOFF64
-		    " to device handle %d\n", rc, cnt, ba, devcon->devmap_handle);
+		printf("Error %d writing %zu blocks starting at block %" PRIuOFF64
+		    " to device handle %" PRIun "\n", rc, cnt, ba, devcon->devmap_handle);
 #ifndef NDEBUG
 		stacktrace_print();
