code review 5489100: go/build: add new +build tags 'cgo' and 'nocgo'

go/build: add new +build tags 'cgo' and 'nocgo'

This lets us mark net's cgo_stub.go as only to be
built when cgo is disabled.

[rsc, 2011-12-21 12:42:35]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://go.googlecode.com/hg/

[ality, 2011-12-21 13:19:23]

Thanks for doing this.

https://codereview.appspot.com/5489100/diff/8/src/pkg/go/build/dir.go
File src/pkg/go/build/dir.go (right):

https://codereview.appspot.com/5489100/diff/8/src/pkg/go/build/dir.go#newcode98
src/pkg/go/build/dir.go:98: if DefaultContext.GOOS == "openbsd" ||
DefaultContext.GOOS == "netbsd" {
Add plan9.

[rsc, 2011-12-21 13:23:39]

PTAL

Reorganized to list what does work instead of what doesn't.

[ality, 2011-12-21 13:28:42]

LGTM

[mikio, 2011-12-21 13:32:00]

It's very close on openbsd.

ok      flag
ok      fmt
FAIL    go/build
--- FAIL: TestBuild (0.15 seconds)
        build_test.go:71: ScanDir(`go/build/cgotest`) =
&build.DirInfo{Package:"cgotest", PackageComment:(*ast.CommentGroup)(nil),
ImportPath:"", Imports:[]string{"C", "unsafe"}, GoFiles:[]string(nil),
HFiles:[]string{"cgotest.h"}, CFiles:[]string{"cgotest.c"},
SFiles:[]string(nil), CgoFiles:[]string(nil), CgoPkgConfig:[]string(nil),
CgoCFLAGS:[]string(nil), CgoLDFLAGS:[]string(nil), TestGoFiles:[]string(nil),
XTestGoFiles:[]string(nil), TestImports:[]string{}}, want
&build.DirInfo{Package:"cgotest", PackageComment:(*ast.CommentGroup)(nil),
ImportPath:"", Imports:[]string{"C", "unsafe"}, GoFiles:[]string(nil),
HFiles:[]string{"cgotest.h"}, CFiles:[]string{"cgotest.c"},
SFiles:[]string(nil), CgoFiles:[]string{"cgotest.go"},
CgoPkgConfig:[]string(nil), CgoCFLAGS:[]string(nil), CgoLDFLAGS:[]string(nil),
TestGoFiles:[]string(nil), XTestGoFiles:[]string(nil), TestImports:[]string{}}
FAIL

[rsc, 2011-12-21 13:40:36]

PTAL

Thanks for the report.

[mikio, 2011-12-21 13:47:53]

LGTM

OpenBSD is back.

[rsc, 2011-12-21 13:51:22]

*** Submitted as http://code.google.com/p/go/source/detail?r=a6f76d1d70f4 ***

go/build: add new +build tags 'cgo' and 'nocgo'

This lets us mark net's cgo_stub.go as only to be
built when cgo is disabled.

R=golang-dev, ality, mikioh.mikioh
CC=golang-dev
http://codereview.appspot.com/5489100