net: Dial("tcp", "addr:port") fails on Windows

[weiyixuan]

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

$ go version
go version go1.11.3 windows/amd64

Does this issue reproduce with the latest release?

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

go env Output

$ go env
set GOARCH=amd64
set GOBIN=
set GOCACHE=C:\Users\Caleb\AppData\Local\go-build
set GOEXE=.exe
set GOFLAGS=
set GOHOSTARCH=amd64
set GOHOSTOS=windows
set GOOS=windows
set GOPATH=C:\Users\Caleb\go
set GOPROXY=
set GORACE=
set GOROOT=C:\Go
set GOTMPDIR=
set GOTOOLDIR=C:\Go\pkg\tool\windows_amd64
set GCCGO=gccgo
set CC=gcc
set CXX=g++
set CGO_ENABLED=1
set GOMOD=
set CGO_CFLAGS=-g -O2
set CGO_CPPFLAGS=
set CGO_CXXFLAGS=-g -O2
set CGO_FFLAGS=-g -O2
set CGO_LDFLAGS=-g -O2
set PKG_CONFIG=pkg-config
set GOGCCFLAGS=-m64 -mthreads -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=C:\Users\Caleb\AppData\Local\Temp\go-build366274902=/tmp/go-build -gno-record-gcc-switches

What did you do?

var netAddr net.Addr
netAddr = &net.TCPAddr{}
netAddr.(*net.TCPAddr).IP = net.ParseIP("172.20.32.62")
dialer := net.Dialer{LocalAddr: netAddr}
dialer.Dial(network, address)

What did you expect to see?

dialer.Dial should not cause error

What did you see instead?

(Firewall closed)
dial tcp 192.168.31.193:0->222.73.182.66:80: connectex: The requested address is not valid in its context.
dial tcp 192.168.31.193:0->42.81.100.253:80: connectex: The requested address is not valid in its context.
dial tcp 192.168.31.193:0->112.65.249.214:80: connectex: The requested address is not valid in its context.

[imkos]

https://golang.google.cn/pkg/net/

[bcmills]

@weiyixuan, the example you provided is incomplete: it refers to an address variable, but there is no such variable defined in the code snippet.

Please provide a self-contained code example that illustrates the problem.