diff --git a/test/fixedbugs/issue15470.dir/a.go b/test/fixedbugs/issue15470.dir/a.go
new file mode 100644
index 00000000000..1fcf3ea6e01
--- /dev/null
+++ b/test/fixedbugs/issue15470.dir/a.go
@@ -0,0 +1,24 @@
+package a
+
+import "io"
+
+type T interface {
+	M0(_ int)
+	M1(x, _ int) // _ (blank) caused crash
+	M2() (x, _ int)
+}
+
+type S struct{}
+
+func (S) M0(_ int) {}
+func (S) M1(x, _ int) {}
+func (S) M2() (x, _ int) { return }
+func (_ S) M3() {}
+
+// Snippet from x/tools/godoc/analysis/analysis.go.
+// Offending code from #5470.
+type Link interface {
+	Start() int
+	End() int
+	Write(w io.Writer, _ int, start bool) // _ (blank) caused crash
+}
diff --git a/test/fixedbugs/issue15470.dir/b.go b/test/fixedbugs/issue15470.dir/b.go
new file mode 100644
index 00000000000..863ee9f5221
--- /dev/null
+++ b/test/fixedbugs/issue15470.dir/b.go
@@ -0,0 +1,3 @@
+package b
+
+import _ "./a" // must not fail
diff --git a/test/fixedbugs/issue15470.go b/test/fixedbugs/issue15470.go
new file mode 100644
index 00000000000..22b48fe2573
--- /dev/null
+++ b/test/fixedbugs/issue15470.go
@@ -0,0 +1,10 @@
+// compiledir
+
+// Copyright 2016 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 15470: Make sure special-case signatures can
+// be exported and imported w/o problems.
+
+package ignored