Initial commit: Go 1.23 release state

test/fixedbugs/issue4448.go

@@ -0,0 +1,37 @@
+// run
+
+// Copyright 2012 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 4448: 64-bit indices that are statically known
+// to be bounded make 5g and 8g generate a dangling branch.
+
+package main
+
+const b26 uint64 = 0x022fdd63cc95386d
+
+var bitPos [64]int
+
+func init() {
+	for p := uint(0); p < 64; p++ {
+		bitPos[b26<<p>>58] = int(p)
+	}
+}
+
+func MinPos(w uint64) int {
+	if w == 0 {
+		panic("bit: MinPos(0) undefined")
+	}
+	return bitPos[((w&-w)*b26)>>58]
+}
+
+func main() {
+	const one = uint64(1)
+	for i := 0; i < 64; i++ {
+		if MinPos(1<<uint(i)) != i {
+			println("i =", i)
+			panic("MinPos(1<<uint(i)) != i")
+		}
+	}
+}