Initial commit: Go 1.23 release state

test/fixedbugs/notinheap3.go

@@ -0,0 +1,80 @@
+// errorcheck -+ -0 -l -d=wb
+
+// 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.
+
+// Test write barrier elimination for notinheap.
+
+//go:build cgo
+
+package p
+
+import "runtime/cgo"
+
+type t1 struct {
+	x *nih
+	s []nih
+	y [1024]byte // Prevent write decomposition
+}
+
+type t2 struct {
+	x *ih
+	s []ih
+	y [1024]byte
+}
+
+type nih struct {
+	_ cgo.Incomplete
+	x uintptr
+}
+
+type ih struct { // In-heap type
+	x uintptr
+}
+
+var (
+	v1 t1
+	v2 t2
+
+	v1s []t1
+	v2s []t2
+)
+
+func f() {
+	// Test direct writes
+	v1.x = nil        // no barrier
+	v2.x = nil        // ERROR "write barrier"
+	v1.s = []nih(nil) // no barrier
+	v2.s = []ih(nil)  // ERROR "write barrier"
+}
+
+func g() {
+	// Test aggregate writes
+	v1 = t1{x: nil} // no barrier
+	v2 = t2{x: nil} // ERROR "write barrier"
+}
+
+func h() {
+	// Test copies and appends.
+	copy(v1s, v1s[1:])      // no barrier
+	copy(v2s, v2s[1:])      // ERROR "write barrier"
+	_ = append(v1s, v1s...) // no barrier
+	_ = append(v2s, v2s...) // ERROR "write barrier"
+}
+
+// Slice clearing
+
+var (
+	sliceIH  []*ih
+	sliceNIH []*nih
+)
+
+func sliceClear() {
+	for i := range sliceIH {
+		sliceIH[i] = nil // ERROR "write barrier"
+	}
+	for i := range sliceNIH {
+		sliceNIH[i] = nil // no barrier
+	}
+}