code review 140440044: runtime: fix windows/386 build

runtime: fix windows/386 build

The difference between the old and the new (from earlier) code
is that we set stackguard = stack.lo + StackGuard, while the old
code set stackguard = stack.lo. That 512 bytes appears to be
the difference between the profileloop function running and not running.

We don't know how big the system stack is, but it is likely MUCH bigger than 4k.
Give Go/C 8k.

[rsc, 2014-09-09 21:12:03]

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

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

[rsc, 2014-09-09 21:12:08]

*** Submitted as https://code.google.com/p/go/source/detail?r=a734060a64b9 ***

runtime: fix windows/386 build

The difference between the old and the new (from earlier) code
is that we set stackguard = stack.lo + StackGuard, while the old
code set stackguard = stack.lo. That 512 bytes appears to be
the difference between the profileloop function running and not running.

We don't know how big the system stack is, but it is likely MUCH bigger than 4k.
Give Go/C 8k.

TBR=iant
CC=golang-codereviews
https://codereview.appspot.com/140440044

[gobot, 2014-09-09 21:16:39]

This CL appears to have broken the linux-386 builder.
See http://build.golang.org/log/c6bc2866c5ef017c6f43a9c4f860cf3f9c7e301e

[iant, 2014-09-09 21:29:08]

LGTM