diff --git a/src/cmd/gc/walk.c b/src/cmd/gc/walk.c
index 68bd01cda07..6ec978f0bb2 100644
--- a/src/cmd/gc/walk.c
+++ b/src/cmd/gc/walk.c
@@ -876,6 +876,7 @@ walkexpr(Node **np, NodeList **init)
 				// delayed until now because "abc"[2] is not
 				// an ideal constant.
 				nodconst(n, n->type, n->left->val.u.sval->s[v]);
+				n->typecheck = 1;
 			}
 		}
 		goto ret;
diff --git a/test/fixedbugs/bug399.go b/test/fixedbugs/bug399.go
new file mode 100644
index 00000000000..25f6351e068
--- /dev/null
+++ b/test/fixedbugs/bug399.go
@@ -0,0 +1,15 @@
+// $G $D/$F.go || echo "Bug399"
+
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 2674
+
+package main
+const dow = "\000\003"
+
+func main() {
+	println(int(dow[1]))
+}
+