Initial commit: Go 1.23 release state

test/fixedbugs/issue67255.go

@@ -0,0 +1,33 @@
+// run
+
+// Copyright 2024 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
+
+var zero int
+
+var sink any
+
+func main() {
+	var objs [][]*byte
+	for i := 10; i < 200; i++ {
+		// The objects we're allocating here are pointer-ful. Some will
+		// max out their size class, which are the ones we want.
+		// We also allocate from small to large, so that the object which
+		// maxes out its size class is the last one allocated in that class.
+		// This allocation pattern leaves the next object in the class
+		// unallocated, which we need to reproduce the bug.
+		objs = append(objs, make([]*byte, i))
+	}
+	sink = objs // force heap allocation
+
+	// Bug will happen as soon as the write barrier turns on.
+	for range 10000 {
+		sink = make([]*byte, 1024)
+		for _, s := range objs {
+			s = append(s, make([]*byte, zero)...)
+		}
+	}
+}