diff --git a/src/cmd/6l/obj.c b/src/cmd/6l/obj.c
index a7ef58db47..3ef8027fa9 100644
--- a/src/cmd/6l/obj.c
+++ b/src/cmd/6l/obj.c
@@ -462,7 +462,7 @@ loop:
 			sig = 1729;
 		if(sig != 0){
 			if(s->sig != 0 && s->sig != sig)
-				diag("incompatible type signatures"
+				diag("incompatible type signatures "
 					"%ux(%s) and %ux(%s) for %s",
 					s->sig, s->file, sig, pn, s->name);
 			s->sig = sig;
diff --git a/src/cmd/8l/obj.c b/src/cmd/8l/obj.c
index 297b5bed55..c2f409e91d 100644
--- a/src/cmd/8l/obj.c
+++ b/src/cmd/8l/obj.c
@@ -480,7 +480,7 @@ loop:
 			sig = 1729;
 		if(sig != 0){
 			if(s->sig != 0 && s->sig != sig)
-				diag("incompatible type signatures"
+				diag("incompatible type signatures "
 					"%ux(%s) and %ux(%s) for %s",
 					s->sig, s->file, sig, pn, s->name);
 			s->sig = sig;