diff --git a/src/reflect/all_test.go b/src/reflect/all_test.go
index 0a1a38dd2ed..e51d19efdd6 100644
--- a/src/reflect/all_test.go
+++ b/src/reflect/all_test.go
@@ -1631,6 +1631,15 @@ func TestFunc(t *testing.T) {
 	}
 }
 
+func TestCallConvert(t *testing.T) {
+	v := ValueOf(new(io.ReadWriter)).Elem()
+	f := ValueOf(func(r io.Reader) io.Reader { return r })
+	out := f.Call([]Value{v})
+	if len(out) != 1 || out[0].Type() != TypeOf(new(io.Reader)).Elem() || !out[0].IsNil() {
+		t.Errorf("expected [nil], got %v", out)
+	}
+}
+
 type emptyStruct struct{}
 
 type nonEmptyStruct struct {
diff --git a/src/reflect/value.go b/src/reflect/value.go
index 0184e6820ec..d3575cae6b7 100644
--- a/src/reflect/value.go
+++ b/src/reflect/value.go
@@ -2197,6 +2197,12 @@ func (v Value) assignTo(context string, dst *rtype, target unsafe.Pointer) Value
 		if target == nil {
 			target = unsafe_New(dst)
 		}
+		if v.Kind() == Interface && v.IsNil() {
+			// A nil ReadWriter passed to nil Reader is OK,
+			// but using ifaceE2I below will panic.
+			// Avoid the panic by returning a nil dst (e.g., Reader) explicitly.
+			return Value{dst, nil, flag(Interface)}
+		}
 		x := valueInterface(v, false)
 		if dst.NumMethod() == 0 {
 			*(*interface{})(target) = x