go - 什么时候 int 是 64 位的？

Question

根据doc :

int is a signed integer type that is at least 32 bits in size. It is a distinct type, however, and not an alias for, say, int32.

但它没有说哪个平台或什么时候会比 int32 更大。

谁能给我更多详细信息？或者处理它的源代码在哪里？我可以强制编译器生成 64 位 int 吗？

我知道我可以使用 int64。这不是要求最佳实践的问题。

Answer 1

The Go Programming Language Specification

Numeric types

There is also a set of predeclared numeric types with implementation-specific sizes:

uint     either 32 or 64 bits
int      same size as uint

---

int 的大小取决于编译器作者。它通常是主机的自然、有效的大小。例如，amd64 上为 64 位，386 架构上为 32 位。

---

例如，

package main

import (
    "fmt"
    "runtime"
    "strconv"
)

func main() {
    fmt.Println(runtime.GOARCH, strconv.IntSize)
}

输出:

$ uname -p
x86_64
$ go run intsize.go
amd64 64
$ 

---

Playground :https://play.golang.org/p/wyNm2Hyzl6W

输出:

amd64p32 32

The Go Blog: Inside the Go Playground

---

Go 从 C 继承了这个。

The C Programming Language, 2nd Edition, Brian W. Kernighan and Dennis Ritchie

int an integer, typically reflecting the natural size of integers on the host machine