code review 6826079: cmd/6c, cmd/8c: use signed char explicitly in mul.c

cmd/6c, cmd/8c: use signed char explicitly in mul.c

On ARM, char is unsigned, and the code generation for
multiplication gets totally broken.

Fixes issue 4354.

[remyoudompheng, 2012-11-09 04:32:02]

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

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

[remyoudompheng, 2012-11-09 04:33:47]

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

Please take another look.

[dave_cheney.net, 2012-11-09 04:56:16]

On 2012/11/09 04:33:47, remyoudompheng wrote:
> Hello mailto:golang-dev@googlegroups.com (cc:
mailto:golang-dev@googlegroups.com),
> 
> Please take another look.

Thanks Rémy. With this change I was able to cross compile from linux/arm to
linux/{amd64,386} successfully.

I tested some of the tools produced in $GOROOT/pkg/linux_{amd64,386}/ by copying
them to an intel machine and they worked as expected.

[dave_cheney.net, 2012-11-09 05:49:42]

LGTM, but please wait for rsc and/or minux.

[r, 2012-11-09 06:13:27]

LGTM

[r, 2012-11-09 06:13:40]

LGTM but you should probably wait for rsc

[minux1, 2012-11-09 06:13:52]

LGTM.

I didn't test on ARM, instead i added -funsigned-char to cflags to
cmd/dist/build.c, and verified that only with this CL, all.bash passed
(both GOARCH=386 and GOARCH=amd64).

Thank you for fixing this.

[rsc, 2012-11-09 15:15:06]

LGTM

[remyoudompheng, 2012-11-09 20:06:53]

*** Submitted as http://code.google.com/p/go/source/detail?r=e9a8a01f5d33 ***

cmd/6c, cmd/8c: use signed char explicitly in mul.c

On ARM, char is unsigned, and the code generation for
multiplication gets totally broken.

Fixes issue 4354.

R=golang-dev, dave, minux.ma, rsc
CC=golang-dev
http://codereview.appspot.com/6826079