code review 8465043: cmd/cgo: record CGO_LDFLAGS env var in _cgo_flags

cmd/cgo: record CGO_LDFLAGS env var in _cgo_flags

cgo stores cgo LDFLAGS in _cgo_flags and _cgo_defun.c.
The _cgo_defun.c records the flags via
"#pragma cgo_ldflag <flag>", which external linking
relies upon for passing libraries (and search paths)
to the host linker.

The go command will allow LDFLAGS for cgo to be passed
through the environment (CGO_LDFLAGS); cgo ignores
this environment variable, and so its value doesn't
make it into the above mentioned files. This CL changes
cgo to record CGO_LDFLAGS also.

Fixes issue 5205.

[axw, 2013-04-07 11:42:27]

Hello iant@golang.org (cc: golang-dev@googlegroups.com),

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

[minux1, 2013-04-07 16:04:35]

Fixes issue 5205.

Do we need to support embedded space in $CGO_LDFLAGS?

[axw, 2013-04-07 23:42:49]

On 2013/04/07 16:04:35, minux wrote:
> Fixes issue 5205.
> 
> Do we need to support embedded space in $CGO_LDFLAGS?

Yes, sorry, I should have used splitQuoted. Will fix it this evening when I get
home from work.

[axw, 2013-04-08 12:02:37]

Hello iant@golang.org, minux.ma@gmail.com (cc: golang-dev@googlegroups.com),

Please take another look.

[minux1, 2013-04-08 12:44:15]

LGTM.

Please add "Fixes issue 5205." to the CL description.

[axw, 2013-04-08 13:47:48]

On 2013/04/08 12:44:15, minux wrote:
> LGTM.
> 
> Please add "Fixes issue 5205." to the CL description.

Done. Sorry - I thought your comment would take care of that.
I don't have commit rights, can you please submit it for me?

[minux1, 2013-04-08 14:45:37]

On Mon, Apr 8, 2013 at 9:47 PM,  <axwalk@gmail.com> wrote:
> I don't have commit rights, can you please submit it for me?
Thank you for fixing this. I will take care of submitting this CL.

Will wait some time in case iant (or anyone) has further comments.

[iant, 2013-04-08 18:28:45]

LGTM

Thanks.

[minux1, 2013-04-08 23:35:19]

*** Submitted as https://code.google.com/p/go/source/detail?r=38bb920f0beb ***

cmd/cgo: record CGO_LDFLAGS env var in _cgo_flags

cgo stores cgo LDFLAGS in _cgo_flags and _cgo_defun.c.
The _cgo_defun.c records the flags via
"#pragma cgo_ldflag <flag>", which external linking
relies upon for passing libraries (and search paths)
to the host linker.

The go command will allow LDFLAGS for cgo to be passed
through the environment (CGO_LDFLAGS); cgo ignores
this environment variable, and so its value doesn't
make it into the above mentioned files. This CL changes
cgo to record CGO_LDFLAGS also.

Fixes issue 5205.

R=iant, minux.ma
CC=golang-dev
https://codereview.appspot.com/8465043

Committer: Shenghou Ma <minux.ma@gmail.com>