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// +build !nacl,!js,disabled_see_issue_18589
// buildrun -t 10 -gcflags=-d=ssa/insert_resched_checks/on,ssa/check/on
// Copyright 2016 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.
// Test is disabled because it flakes when run in all.bash
// on some platforms, but is useful standalone to verify
// that rescheduling checks are working (and we may wish
// to investigate the flake, since it suggests that the
// loop rescheduling check may not work right on those
// platforms).
// This checks to see that call-free infinite loops do not
// block garbage collection. IF YOU RUN IT STANDALONE without
// -gcflags=-d=ssa/insert_resched_checks/on in a not-experimental
// build, it should hang.
package main
import (
"runtime"
)
var someglobal1 int
var someglobal2 int
var someglobal3 int
//go:noinline
func f() {}
func standinacorner1() {
for someglobal1&1 == 0 {
someglobal1++
someglobal1++
}
}
func standinacorner2(i int) {
// contains an irreducible loop containing changes to memory
if i != 0 {
goto midloop
}
loop:
if someglobal2&1 != 0 {
goto done
}
someglobal2++
midloop:
someglobal2++
goto loop
done:
return
}
func standinacorner3() {
for someglobal3&1 == 0 {
if someglobal3&2 != 0 {
for someglobal3&3 == 2 {
someglobal3++
someglobal3++
someglobal3++
someglobal3++
}
}
someglobal3++
someglobal3++
someglobal3++
someglobal3++
}
}
func main() {
go standinacorner1()
go standinacorner2(0)
go standinacorner3()
// println("About to stand in a corner1")
for someglobal1 == 0 {
runtime.Gosched()
}
// println("About to stand in a corner2")
for someglobal2 == 0 {
runtime.Gosched()
}
// println("About to stand in a corner3")
for someglobal3 == 0 {
runtime.Gosched()
}
// println("About to GC")
runtime.GC()
// println("Success")
}
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