cmd/compile: fix stencil call expression

In CL 349613,we have supported types.IdentityStrict() that does strict
type comparison.
Therefore, OCONVNOP becomes a possible case in call.X.Op().

Fixes #48604

Change-Id: Ibab27ffcf09656e3380314662f05f38294c1c6ed
Reviewed-on: https://go-review.googlesource.com/c/go/+/351857
Trust: Dan Scales <danscales@google.com>
Trust: David Chase <drchase@google.com>
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>

diff --git a/src/cmd/compile/internal/noder/stencil.go b/src/cmd/compile/internal/noder/stencil.go
index d5fb9f338cd39d17c6e5cfe5b4596fb77f1b3d73..bc142e69856e31b9f5dd21ad7a4b6cbfce4db8e9 100644 (file)
--- a/src/cmd/compile/internal/noder/stencil.go
+++ b/src/cmd/compile/internal/noder/stencil.go
@@ -1093,6 +1093,9 @@ func (subst *subster) node(n ir.Node) ir.Node {
                        case ir.OCALL, ir.OCALLFUNC, ir.OCALLMETH, ir.OCALLINTER:
                                transformCall(call)
 
+                       case ir.OCONVNOP:
+                               transformCall(call)
+
                        case ir.OFUNCINST:
                                // A call with an OFUNCINST will get transformed
                                // in stencil() once we have created & attached the

diff --git a/test/typeparam/issue48604.go b/test/typeparam/issue48604.go
new file mode 100644 (file)
index 0000000..1babd3f
--- /dev/null
+++ b/test/typeparam/issue48604.go
@@ -0,0 +1,25 @@
+// build -gcflags=-G=3
+
+// Copyright 2021 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.
+
+package main
+
+type Foo[T any] interface {
+       CreateBar() Bar[T]
+}
+
+type Bar[T any] func() Bar[T]
+
+func (f Bar[T]) CreateBar() Bar[T] {
+       return f
+}
+
+func abc[R any]() {
+       var _ Foo[R] = Bar[R](nil)()
+}
+
+func main() {
+       abc[int]()
+}
\ No newline at end of file