avoid signed<->unsigned warning
diff --git a/coreutils/chown.c b/coreutils/chown.c
index 660d089..66add48 100644
--- a/coreutils/chown.c
+++ b/coreutils/chown.c
@@ -26,8 +26,8 @@
 		void ATTRIBUTE_UNUSED *junk)
 {
 	if (!chown_func(fileName,
-				(uid == -1) ? statbuf->st_uid : uid,
-				(gid == -1) ? statbuf->st_gid : gid)) {
+				(uid == (uid_t)-1) ? statbuf->st_uid : uid,
+				(gid == (gid_t)-1) ? statbuf->st_gid : gid)) {
 		return TRUE;
 	}
 	bb_perror_msg("%s", fileName);	/* A filename could have % in it... */
diff --git a/coreutils/dd.c b/coreutils/dd.c
index 9a149e2..cba9085 100644
--- a/coreutils/dd.c
+++ b/coreutils/dd.c
@@ -167,7 +167,7 @@
 		if (n == 0) {
 			break;
 		}
-		if (n == bs) {
+		if ((size_t)n == bs) {
 			in_full++;
 		} else {
 			in_part++;
@@ -180,7 +180,7 @@
 		if (n < 0) {
 			bb_perror_msg_and_die("%s", outfile);
 		}
-		if (n == bs) {
+		if ((size_t)n == bs) {
 			out_full++;
 		} else {
 			out_part++;
diff --git a/coreutils/du.c b/coreutils/du.c
index 3778f08..d453ba4 100644
--- a/coreutils/du.c
+++ b/coreutils/du.c
@@ -56,7 +56,7 @@
 #endif
 
 static int max_print_depth = INT_MAX;
-static int count_hardlinks = 1;
+static nlink_t count_hardlinks = 1;
 
 static int status
 #if EXIT_SUCCESS == 0