code review 123040043: cmd/link: fix testdata generation

cmd/link: fix testdata generation

Fixes issue 8494.

[mdempsky, 2014-08-07 19:43:34]

Hello golang-codereviews@googlegroups.com,

I'd like you to review this change to
https://code.google.com/p/go

[mdempsky, 2014-08-14 07:06:58]

Ping?  Issue 8494 (fixed by this CL) is blocking me from mailing out
https://codereview.appspot.com/126790043/ to fix issue 8092.

[gobot, 2014-08-14 16:19:35]

R=rsc@golang.org (assigned by iant@golang.org)

[esk, 2014-08-15 02:47:29]

https://codereview.appspot.com/123040043/diff/80001/src/cmd/link/testdata/Mak...
File src/cmd/link/testdata/Makefile (right):

https://codereview.appspot.com/123040043/diff/80001/src/cmd/link/testdata/Mak...
src/cmd/link/testdata/Makefile:12: GOARCH=amd64 GOOS=darwin go tool 6a
-trimpath=$$PWD $*.s
Did you mean to include this in your CL?

[mdempsky, 2014-08-15 04:07:38]

https://codereview.appspot.com/123040043/diff/80001/src/cmd/link/testdata/Mak...
File src/cmd/link/testdata/Makefile (right):

https://codereview.appspot.com/123040043/diff/80001/src/cmd/link/testdata/Mak...
src/cmd/link/testdata/Makefile:12: GOARCH=amd64 GOOS=darwin go tool 6a
-trimpath=$$PWD $*.s
On 2014/08/15 02:47:29, esk wrote:
> Did you mean to include this in your CL?

Yep, it's the titular change that actually fixes testdata generation for the
general $USER != "rsc" case. :-)

GOARCH=amd64 is necessary to be able to use 6a on !amd64 (I think; at least 8a
complains on amd64 if I don't set GOARCH=386).

GOOS=darwin is a bit optional, but it fixes an unnecessary variation between
generated .6 files across platforms.  Also, cmd/ld complains when an object
file's goos value doesn't match the target OS when linking, and link_test.go is
specifically trying to link a darwin executable.  Though cmd/link currently
doesn't enforce this (presumably since currently it only supports darwin
anyway).

-trimpath=$$PWD is so that the generated files won't contain the full path
information like "/Users/rsc/g/go/src/cmd/link/testdata/", which causes the
files to unnecessarily change depending on where your source tree is.

[rsc, 2014-08-25 00:30:14]

LGTM

https://codereview.appspot.com/123040043/diff/80001/src/cmd/link/testdata/Mak...
File src/cmd/link/testdata/Makefile (right):

https://codereview.appspot.com/123040043/diff/80001/src/cmd/link/testdata/Mak...
src/cmd/link/testdata/Makefile:12: GOARCH=amd64 GOOS=darwin go tool 6a
-trimpath=$$PWD $*.s
use $(shell pwd)
not everyone uses a shell that sets $PWD.

[rsc, 2014-08-25 00:31:11]

*** Submitted as https://code.google.com/p/go/source/detail?r=7db430d2938c ***

cmd/link: fix testdata generation

Fixes issue 8494.

LGTM=rsc
R=golang-codereviews, gobot, rsc, evankroske
CC=golang-codereviews
https://codereview.appspot.com/123040043

Committer: Russ Cox <rsc@golang.org>

[gobot, 2014-08-25 04:35:21]

This CL appears to have broken the linux-386 builder.
See http://build.golang.org/log/8949a3286f0dd5377ca7dd03733a29c0733d6a38

[mdempsky, 2014-08-27 17:56:52]

https://codereview.appspot.com/123040043/diff/80001/src/cmd/link/testdata/Mak...
File src/cmd/link/testdata/Makefile (right):

https://codereview.appspot.com/123040043/diff/80001/src/cmd/link/testdata/Mak...
src/cmd/link/testdata/Makefile:12: GOARCH=amd64 GOOS=darwin go tool 6a
-trimpath=$$PWD $*.s
On 2014/08/25 00:30:14, rsc wrote:
> use $(shell pwd)
> not everyone uses a shell that sets $PWD.

Fair enough.  Thanks for applying that change and committing!