From 73df946d56c74384511a194dd01dbe099584fd1a Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 15:14:23 +0200 Subject: Adding upstream version 1.16.10. Signed-off-by: Daniel Baumann --- test/fixedbugs/issue40629.go | 69 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 test/fixedbugs/issue40629.go (limited to 'test/fixedbugs/issue40629.go') diff --git a/test/fixedbugs/issue40629.go b/test/fixedbugs/issue40629.go new file mode 100644 index 0000000..c6ef408 --- /dev/null +++ b/test/fixedbugs/issue40629.go @@ -0,0 +1,69 @@ +// run + +// Copyright 2020 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. + +package main + +import "fmt" + +const N = 40 + +func main() { + var x [N]int // stack-allocated memory + for i := range x { + x[i] = 0x999 + } + + // This defer checks to see if x is uncorrupted. + defer func(p *[N]int) { + recover() + for i := range p { + if p[i] != 0x999 { + for j := range p { + fmt.Printf("p[%d]=0x%x\n", j, p[j]) + } + panic("corrupted stack variable") + } + } + }(&x) + + // This defer starts a new goroutine, which will (hopefully) + // overwrite x on the garbage stack. + defer func() { + c := make(chan bool) + go func() { + useStack(1000) + c <- true + }() + <-c + + }() + + // This defer causes a stack copy. + // The old stack is now garbage. + defer func() { + useStack(1000) + }() + + // Trigger a segfault. + *g = 0 + + // Make the return statement unreachable. + // That makes the stack map at the deferreturn call empty. + // In particular, the argument to the first defer is not + // marked as a pointer, so it doesn't get adjusted + // during the stack copy. + for { + } +} + +var g *int64 + +func useStack(n int) { + if n == 0 { + return + } + useStack(n - 1) +} -- cgit v1.2.3