code review 5672080: cmd/cgo: bug fixes

cmd/cgo: bug fixes

* disallow embedding of C type (Fixes issue 2552)
* detect 0-length array (Fixes issue 2806)
* use typedefs when possible, to avoid attribute((unavailable)) (Fixes issue 2888)
* print Go types constructed from C types using original C types (Fixes issue 2612)

This fix changes _cgo_export.h to repeat the preamble from import "C".
Otherwise the fix to issue 2612 is impossible, since it cannot refer to
types that have not been defined.  If people are using //export and
putting non-header information in the preamble, they will need to
refactor their code.

[rsc, 2012-02-17 19:14:47]

Hello golang-dev@googlegroups.com,

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

[r2, 2012-02-17 20:30:44]

does go1.tmpl need words about cgo?

-rob

[rsc, 2012-02-18 19:53:39]

Hello golang-dev@googlegroups.com, r@google.com (cc:
golang-dev@googlegroups.com),

Please take another look.

[r, 2012-02-19 06:01:19]

LGTM

http://codereview.appspot.com/5672080/diff/1016/doc/go1.tmpl
File doc/go1.tmpl (right):

http://codereview.appspot.com/5672080/diff/1016/doc/go1.tmpl#newcode1710
doc/go1.tmpl:1710: The <a href="/cmd/cgo">cgo command</a>
In Go 1, the <a href="/cmd/cgo">cgo command</a> uses a different
<code>_cgo_export.h</code> file, which is...

[rsc, 2012-02-19 18:32:57]

*** Submitted as 00a19a04b13e ***

cmd/cgo: bug fixes

* disallow embedding of C type (Fixes issue 2552)
* detect 0-length array (Fixes issue 2806)
* use typedefs when possible, to avoid attribute((unavailable)) (Fixes issue
2888)
* print Go types constructed from C types using original C types (Fixes issue
2612)

This fix changes _cgo_export.h to repeat the preamble from import "C".
Otherwise the fix to issue 2612 is impossible, since it cannot refer to
types that have not been defined.  If people are using //export and
putting non-header information in the preamble, they will need to
refactor their code.

R=golang-dev, r, r
CC=golang-dev
http://codereview.appspot.com/5672080

[albert.strasheim, 2012-02-20 05:23:21]

Hello

On 2012/02/19 18:32:57, rsc wrote:
> *** Submitted as 00a19a04b13e ***
> cmd/cgo: bug fixes

I think this change made a bunch of stuff blow up in our cgo package that wraps
libibverbs.

ib/_obj/_cgo_gotypes.go:16: invalid recursive type _Ctype_pthread_mutex_t
ib/_obj/_cgo_gotypes.go:16: invalid recursive type _Ctype_union___0
:5[ib/_obj/_cgo_gotypes.go:186]: invalid recursive type _Ctype_union___2
:7[ib/_obj/_cgo_gotypes.go:188]: invalid recursive type _Ctype_union___3
:11[ib/_obj/_cgo_gotypes.go:192]: invalid recursive type _Ctype_union___1
:15[ib/_obj/_cgo_gotypes.go:196]: invalid recursive type _Ctype_union___5
:1[ib/_obj/_cgo_gotypes.go:468]: invalid recursive type _Ctype_union_ibv_gid
:1[ib/_obj/_cgo_gotypes.go:498]: invalid recursive type _Ctype_pthread_cond_t
:1[ib/_obj/_cgo_gotypes.go:498]: invalid recursive type _Ctype_union___4
interface.go:73[ib/_obj/interface.cgo1.go:98]: cannot slice gid (type
_Ctype_union_ibv_gid)
interface.go:73[ib/_obj/interface.cgo1.go:98]: too many errors

Some of the error messages seem to be missing filenames...

The header file in question is this one:

http://git.kernel.org/?p=libs/infiniband/libibverbs.git;a=blob;f=include/infi...

Regards

Albert

[mattn, 2012-02-21 01:11:49]

I also failed to compile go-gtk.