diff --git a/mach/proto/cg/fillem.c b/mach/proto/cg/fillem.c
index 3a365ec70..e33439fdc 100644
--- a/mach/proto/cg/fillem.c
+++ b/mach/proto/cg/fillem.c
@@ -1,3 +1,7 @@
+#ifndef NORCSID
+static char rcsid2[] = "$Header$";
+#endif
+
 #include <stdio.h>
 #include "assert.h"
 #include <em_spec.h>
@@ -203,6 +207,7 @@ dopseudo() {
 	case EOF:
 		swtxt();
 		popstr(0);
+		tstoutput();
 		exit(0);
 	default:
 		error("Unknown opcode %d",savetab1);
@@ -330,6 +335,7 @@ dopseudo() {
 #ifdef REGVARS
 		unlinkregs();
 #endif
+		tstoutput();
 		break;
 	default:
 		error("No table entry for %d",savetab1);
diff --git a/mach/proto/cg/gencode.c b/mach/proto/cg/gencode.c
index 8667277b6..ea1ccbe5c 100644
--- a/mach/proto/cg/gencode.c
+++ b/mach/proto/cg/gencode.c
@@ -1,3 +1,7 @@
+#ifndef NORCSID
+static char rcsid[] = "$Header$";
+#endif
+
 #include "assert.h"
 #include <stdio.h>
 #include "param.h"
@@ -59,6 +63,12 @@ out_finish() {
 		fclose(codefile);
 }
 
+tstoutput() {
+
+	if (ferror(codefile))
+		error("Write error on output");
+}
+
 gencode(code) register char *code; {
 	register c;
 	int tokno,fldno,insno,regno,subno;