gcc/libgo/misc/cgo/gmp/fib.go
Ian Lance Taylor 8dc2499aa6 libgo: update to Go1.18beta2
gotools/
	* Makefile.am (go_cmd_cgo_files): Add ast_go118.go
	(check-go-tool): Copy golang.org/x/tools directories.
	* Makefile.in: Regenerate.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/384695
2022-02-11 15:01:19 -08:00

47 lines
936 B
Go

// Copyright 2009 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.
//go:build ignore
// +build ignore
// Compute Fibonacci numbers with two goroutines
// that pass integers back and forth. No actual
// concurrency, just threads and synchronization
// and foreign code on multiple pthreads.
package main
import (
big "."
"runtime"
)
func fibber(c chan *big.Int, out chan string, n int64) {
// Keep the fibbers in dedicated operating system
// threads, so that this program tests coordination
// between pthreads and not just goroutines.
runtime.LockOSThread()
i := big.NewInt(n)
if n == 0 {
c <- i
}
for {
j := <-c
out <- j.String()
i.Add(i, j)
c <- i
}
}
func main() {
c := make(chan *big.Int)
out := make(chan string)
go fibber(c, out, 0)
go fibber(c, out, 1)
for i := 0; i < 200; i++ {
println(<-out)
}
}