code review 6904061: cmd/gc: prevent ngotype from allocating.

cmd/gc: prevent ngotype from allocating.

[remyoudompheng, 2012-12-09 10:17:46]

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

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

[dave_cheney.net, 2012-12-09 10:25:20]

On 2012/12/09 10:17:46, remyoudompheng wrote:
> Hello mailto:golang-dev@googlegroups.com (cc:
mailto:golang-dev@googlegroups.com),
> 
> I'd like you to review this change to
> https://go.googlecode.com/hg/

/home/dfc/go/src/cmd/gc/reflect.c:698:2: error: data definition has no type or
storage class [-Werror]
/home/dfc/go/src/cmd/gc/reflect.c:698:2: error: type defaults to 'int' in
declaration of 'n' [-Werror=implicit-int]
/home/dfc/go/src/cmd/gc/reflect.c:698:17: error: 's' undeclared here (not in a
function)
/home/dfc/go/src/cmd/gc/reflect.c:699:3: error: expected '=', ',', ';', 'asm' or
'__attribute__' before '->' token
/home/dfc/go/src/cmd/gc/reflect.c:700:3: error: expected '=', ',', ';', 'asm' or
'__attribute__' before '->' token
/home/dfc/go/src/cmd/gc/reflect.c:701:3: error: expected '=', ',', ';', 'asm' or
'__attribute__' before '->' token
/home/dfc/go/src/cmd/gc/reflect.c:702:3: error: expected '=', ',', ';', 'asm' or
'__attribute__' before '->' token
/home/dfc/go/src/cmd/gc/reflect.c:703:2: error: expected identifier or '('
before 'return'
/home/dfc/go/src/cmd/gc/reflect.c:704:1: error: expected identifier or '('
before '}' token
/home/dfc/go/src/cmd/gc/reflect.c: In function 'typename':
/home/dfc/go/src/cmd/gc/reflect.c:696:2: error: control reaches end of non-void
function [-Werror=return-type]
cc1: all warnings being treated as errors

Fails to compile under gcc 4.7.2, linux/arm

[remyoudompheng, 2012-12-09 10:33:17]

Hello golang-dev@googlegroups.com, dave@cheney.net (cc:
golang-dev@googlegroups.com),

Please take another look.

[dave_cheney.net, 2012-12-09 10:44:20]

On 2012/12/09 10:33:17, remyoudompheng wrote:
> Hello mailto:golang-dev@googlegroups.com, mailto:dave@cheney.net (cc:
> mailto:golang-dev@googlegroups.com),
> 
> Please take another look.

Thanks, it now compiles, but I'm having trouble determining any memory savings.
What ratio were you expecting to see ?

[remyoudompheng, 2012-12-09 11:05:10]

On 2012/12/09 10:44:20, dfc wrote:
> Thanks, it now compiles, but I'm having trouble determining any memory
savings.
> What ratio were you expecting to see ?

I suppose it depends on package size because it's called during code generation:
most other memory uses we saw were for imports. On my profile of compilation of
test/rotate.go output, it saves 140MB out of 1.4 GB.

[rsc, 2012-12-09 16:11:15]

LGTM

I don't think it will have a huge difference, but it's good.

[remyoudompheng, 2012-12-09 18:27:37]

*** Submitted as https://code.google.com/p/go/source/detail?r=970e6f92841d ***

cmd/gc: prevent ngotype from allocating.

R=golang-dev, dave, rsc
CC=golang-dev
https://codereview.appspot.com/6904061