diff --git a/include/9p.h b/include/9p.h
index f83dce0..b6e959b 100644
--- a/include/9p.h
+++ b/include/9p.h
@@ -39,7 +39,7 @@
 struct Fid
 {
 	ulong	fid;
-	char		omode;	/* -1 = not open */
+	int		omode;	/* -1 = not open */
 	File*		file;
 	char*	uid;
 	Qid		qid;
diff --git a/include/mach.h b/include/mach.h
index 05b6337..e39d502 100644
--- a/include/mach.h
+++ b/include/mach.h
@@ -481,7 +481,7 @@
 			uint locals;
 			char *dir;
 			char *file;
-			char frameptr;
+			schar frameptr;
 			uint framesize;
 		} stabs;
 	} u;