diff --git a/src/afs/afs.h b/src/afs/afs.h
index 2f39f2b0f6..a54a3173ca 100644
--- a/src/afs/afs.h
+++ b/src/afs/afs.h
@@ -104,7 +104,7 @@ extern afs_int32 afs_rx_idledead;
 struct sysname_info {
     char *name;
     short offset;
-    char index, allocked;
+    signed char index, allocked;
 };
 
 /* flags to use with AFSOP_CACHEINIT */
diff --git a/src/rxkad/rxkad.p.h b/src/rxkad/rxkad.p.h
index 6895b5a2e7..91d1f52087 100644
--- a/src/rxkad/rxkad.p.h
+++ b/src/rxkad/rxkad.p.h
@@ -74,7 +74,7 @@ typedef char rxkad_type;
 #define rxkad_client 1		/* bits definitions */
 #define rxkad_server 2
 
-typedef char rxkad_level;
+typedef signed char rxkad_level;
 #define rxkad_clear 0		/* send packets in the clear */
 #define rxkad_auth 1		/* send encrypted sequence numbers */
 #define rxkad_crypt 2		/* encrypt packet data */
diff --git a/src/volser/vos.c b/src/volser/vos.c
index fbd66c05ba..391ff34fcf 100644
--- a/src/volser/vos.c
+++ b/src/volser/vos.c
@@ -5568,7 +5568,7 @@ ConvertRO(struct cmd_syndesc *as, void *arock)
     afs_int32 ropartition = 0;
     int force = 0;
     struct rx_connection *aconn;
-    char c, dc;
+    int c, dc;
 
     server = GetServer(as->parms[0].items->data);
     if (!server) {