Since we are on the topic, may be interesting to someone: https://dfava.github.io/papers/fava2020finding.pdf
https://dfava.github.io/thesis/dfava_thesis.pdf I’m not so sure I agree with you saying “ whatever the current implementation behavior is” Daniel > On Feb 9, 2022, at 3:45 PM, Robert Engels <reng...@ix.netcom.com> wrote: > > > See issue 5045 > >>> On Feb 9, 2022, at 8:42 AM, Robert Engels <reng...@ix.netcom.com> wrote: >>> >> >> The problem with this reasoning is that Go still does not have an explicit >> memory model with respect to happens before relationships - falling back on >> “whatever the current implementation behavior is”. This makes it more likely >> that any change in the compiler will need to continue to support the benign >> data races. >> >>>> On Feb 9, 2022, at 8:25 AM, peterGo <go.peter...@gmail.com> wrote: >>>> >>> >>> Pelen Li, >>> >>> Boehm covers your specific case: "there is no reason to believe that a >>> currently working program with “benign races” will continue to work when it >>> is recompiled. Perhaps most surprisingly, this includes even the case of >>> potentially concurrent writes of the same value by different threads." >>> >>> Peter >>> >>>> On Wed, Feb 9, 2022 at 9:17 AM peterGo <go.peter...@gmail.com> wrote: >>>> Pelen Li, >>>> >>>> Always fix your data races. You should consider the results of data races >>>> as undefined. >>>> >>>> Dmitry Vyukov, who implemented the Go race detector, once wrote an >>>> interesting article with the title: "Benign data races: what could >>>> possibly go wrong?" >>>> >>>> https://twitter.com/dvyukov/status/288858957827682304 >>>> >>>> The Go Blog: Introducing the Go Race Detector >>>> Dmitry Vyukov and Andrew Gerrand >>>> 26 June 2013 >>>> >>>> https://go.dev/blog/race-detector >>>> >>>> Hans-J. Boehm wrote: "there is no reason to believe that a currently >>>> working program with “benign races” will continue to work when it is >>>> recompiled." >>>> >>>> How to miscompile programs with “benign” data races >>>> Hans-J. Boehm >>>> HP Laboratories >>>> >>>> https://www.usenix.org/legacy/event/hotpar11/tech/final_files/Boehm.pdf >>>> >>>> Nonetheless many programmers clearly believe, along with [15] that certain >>>> kinds of data races can be safely ignored in practice because they will >>>> produce expected results with all reasonable implementations. Here we show >>>> that all kinds of C or C++ source-level “benign” races discussed in the >>>> literature can in fact lead to incorrect execution as a result of >>>> perfectly reasonable compiler transformations, or when the program is >>>> moved to a different hardware platform. Thus there is no reason to believe >>>> that a currently working program with “benign races” will continue to work >>>> when it is recompiled. Perhaps most surprisingly, this includes even the >>>> case of potentially concurrent writes of the same value by different >>>> threads. >>>> >>>> And so on. >>>> >>>> Peter >>>> >>>>> On Wednesday, February 9, 2022 at 3:21:26 AM UTC-5 penglo...@gmail.com >>>>> wrote: >>>>> I want to set a value with the index of the slice. I don't really care if >>>>> there are multiple goroutines cover the value with each other, because >>>>> the value is same. >>>>> >>>>> Can i just ignore this DataRace Warning? I don't know if this will cause >>>>> panic. >>>>> >>>>> Here's my example: >>>>> I defined a structure with slice, and a Add() function for it. sample >>>>> like this: >>>>> ```go >>>>> package test_slice >>>>> >>>>> type SliceObj struct { >>>>> set []uint >>>>> } >>>>> >>>>> func New(length int64) *SliceObj { >>>>> return &SliceObj{ >>>>> set: make([]uint, length), >>>>> } >>>>> } >>>>> >>>>> func (b *SliceObj) Add(i uint) { >>>>> b.set[i] = i >>>>> } >>>>> ``` >>>>> >>>>> And then i make a main file to test it, like this: >>>>> ```go >>>>> package main >>>>> >>>>> import ( >>>>> "time" >>>>> >>>>> "test_slice" >>>>> ) >>>>> >>>>> func main() { >>>>> s := test_slice.New(1000000) >>>>> go func() { >>>>> s.Add(10) >>>>> }() >>>>> s.Add(10) >>>>> >>>>> time.Sleep(3 * time.Second) >>>>> } >>>>> ``` >>>>> >>>>> And data race is detected: >>>>> (I know the reason of this warning, but I don't know if I can ignore it) >>>>> ================== >>>>> WARNING: DATA RACE >>>>> Write at 0x00c000180050 by goroutine 18: >>>>> test_slice.(*SliceObj).Add() >>>>> test_slice.go:27 +0x68 >>>>> main.main.func1() >>>>> test.go:25 +0x36 >>>>> >>>>> Previous write at 0x00c000180050 by main goroutine: >>>>> test_slice.(*SliceObj).Add() >>>>> test_slice.go:27 +0xfd >>>>> main.main() >>>>> test.go:27 +0xcb >>>>> >>>>> Goroutine 18 (running) created at: >>>>> main.main() >>>>> test.go:24 +0xca >>>>> ================== >>>>> Found 1 data race(s) >>>>> exit status 66 >>>> >>>> -- >>>> You received this message because you are subscribed to a topic in the >>>> Google Groups "golang-nuts" group. >>>> To unsubscribe from this topic, visit >>>> https://groups.google.com/d/topic/golang-nuts/ai0eQtnas7A/unsubscribe. >>>> To unsubscribe from this group and all its topics, send an email to >>>> golang-nuts+unsubscr...@googlegroups.com. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/golang-nuts/2594a018-872a-4d54-8ede-c769042e99b5n%40googlegroups.com. >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "golang-nuts" group. >>> To unsubscribe from this group and stop receiving emails from it, send an >>> email to golang-nuts+unsubscr...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/golang-nuts/CAOBWp8do4njo%2B56hb7PJ-4RdXxV%2B0KGUVwv9zRC%3Dgd3bm%2BSM_g%40mail.gmail.com. > -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/golang-nuts/78D7693F-198F-4CDE-BEBE-C296D77111F3%40ix.netcom.com. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. 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