diff --git a/minix/lib/libsys/env_get_prm.c b/minix/lib/libsys/env_get_prm.c
index de6d556b1..b3860b4e6 100644
--- a/minix/lib/libsys/env_get_prm.c
+++ b/minix/lib/libsys/env_get_prm.c
@@ -52,7 +52,7 @@ int env_get_param(const char *key, char *value, int max_len)
   m.m_lsys_krn_sys_getinfo.val_len = sizeof(mon_params);
   m.m_lsys_krn_sys_getinfo.val_ptr = (vir_bytes)mon_params;
   if ((s=_kernel_call(SYS_GETINFO, &m)) != OK) {
-	printf("SYS_GETINFO: %d (size %u)\n", s, sizeof(mon_params));
+	printf("SYS_GETINFO: %d (size %zu)\n", s, sizeof(mon_params));
 	return(s);
   }
 
diff --git a/minix/lib/libvtreefs/inode.c b/minix/lib/libvtreefs/inode.c
index 59328d9b9..3b40f8cb0 100644
--- a/minix/lib/libvtreefs/inode.c
+++ b/minix/lib/libvtreefs/inode.c
@@ -57,7 +57,7 @@ init_inodes(unsigned int inodes, struct inode_stat * stat,
 	}
 
 #if DEBUG
-	printf("VTREEFS: allocated %d+%d+%d bytes\n",
+	printf("VTREEFS: allocated %zu+%zu+%zu bytes\n",
 	    nr_inodes * sizeof(inode[0]),
 	    nr_inodes * sizeof(parent_name_head[0]),
 	    nr_inodes * sizeof(parent_index_head[0]));