What version of Go are you using (go version)?

$ go version
go version go1.13.1 windows/386

Does this issue reproduce with the latest release?

Yes.

What operating system and processor architecture are you using (go env)?

$ go env
set GOHOSTARCH=386
set GOHOSTOS=windows

What did you do?

try test_Stat-con.go to reproduce the issue

package main

import (
	"os"
)

func main() {
	_, err := os.Stat("con")
	if err != nil {
		panic(err)
	}
}

I have debugged and located that GetFileAttributesEx fails on special files like 'con':

and only 'nul':

reserved names
CON, PRN, AUX, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, and LPT9:
https://docs.microsoft.com/zh-cn/windows/win32/fileio/naming-a-file#naming-conventions
CONIN$ and CONOUT$:
https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilea#consoles

ref:
https://github.com/gcc-mirror/gcc/blob/bbcdad768752f5cab6727242515bcd15706acbea/gcc/ada/adaint.c#L1606-L1618

What did you expect to see?

We can access these special Windows files, especially con for printing to stdout.

What did you see instead?

I found sometimes we need to use stdout as a file:
https://github.com/DNSCrypt/dnscrypt-proxy/blob/858957ce91015057a1f6c5a9a24f3ea2beb48537/dnscrypt-proxy/example-dnscrypt-proxy.toml#L339-L341
But con doesn't work.
By doing some research, I located the code here as described.
GetFileAttributesEx and CreateFile of Stat failed on the reserved file name con, and only 'nul' is considered as the special case.