all: drop support for Go 1.16 and Go 1.17

src/internal/itoa/itoa.go

@@ -1,33 +0,0 @@
-// 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.
-
-// Simple conversions to avoid depending on strconv.
-
-package itoa
-
-// Itoa converts val to a decimal string.
-func Itoa(val int) string {
-	if val < 0 {
-		return "-" + Uitoa(uint(-val))
-	}
-	return Uitoa(uint(val))
-}
-
-// Uitoa converts val to a decimal string.
-func Uitoa(val uint) string {
-	if val == 0 { // avoid string allocation
-		return "0"
-	}
-	var buf [20]byte // big enough for 64bit value base 10
-	i := len(buf) - 1
-	for val >= 10 {
-		q := val / 10
-		buf[i] = byte('0' + val - q*10)
-		i--
-		val = q
-	}
-	// val < 10
-	buf[i] = byte('0' + val)
-	return string(buf[i:])
-}