The compiler must be changed with the Set method
so that the buildToolchain gets updated too.

Fixes #3231.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5768044

The old way to find a port was to listen :0 and then
look at what port it picked, close the listener, and then
immediately try to listen on that port.

On some Windows 7 machines that sequence fails at
the second listen, because the first one is still lingering
in the TCP/IP stack somewhere.  (Ironically, most of these
are used in tests of a "second listen", which in this case
ends up being the third listen.)

Instead of this race, just return the listener from the
function, replacing usableLocalPort+Listen with
usableListenPort.

Fixes #3219.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5769045

Forgot this half in https://golang.org/cl/5764044

R=gri
CC=golang-dev
https://golang.org/cl/5770044

Fixes #3234.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5756078

Fixes #3203.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5769043

Goroutines are no longer excluded from init.

Fixes #3232.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5764044

Fixes #3222.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5761044

Fixes #3230.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5753071

The gccgo compiler incorrectly gave an error for this code.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5767043

R=ken2
CC=golang-dev
https://golang.org/cl/5752073

Does not actually test so files.

««« original CL description
misc/cgo: re-enable testso

Also enabled it for darwin.

R=rsc
CC=golang-dev
https://golang.org/cl/5754063

»»»

R=golang-dev, minux.ma, r, f
CC=golang-dev
https://golang.org/cl/5756075

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5757060

Fixes #3143.

R=ken2
CC=golang-dev
https://golang.org/cl/5752070

Let the outer environment filter down to the commands being run.

TBR=r
CC=golang-dev
https://golang.org/cl/5758066

Fixes #3146.

R=ken2
CC=golang-dev
https://golang.org/cl/5756074

Lets us run multifile tests and tests with arguments.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5753068

go get code.google.com/p/gowingui

R=golang-dev, minux.ma, r
CC=golang-dev
https://golang.org/cl/5752067

        Fixes #3190.

R=rsc, tjyang2001, rsc
CC=golang-dev
https://golang.org/cl/5759056

        find() returns -1 when not found.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5752068

R=golang-dev, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/5757059

Fixes #3226.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5756073

I don't know what's out there, but something
is answering to 127.0.71.111:80 on our builder,
so use a different port.

Also insert a check that the dial fails, which
would have diagnosed this problem.

Fixes #3016.

R=golang-dev, mikioh.mikioh, r
CC=golang-dev
https://golang.org/cl/5754062

Also enabled it for darwin.

R=rsc
CC=golang-dev
https://golang.org/cl/5754063

I don't know enough about multicast.
Should this be disabled on all systems, not just Windows?

R=golang-dev
CC=golang-dev
https://golang.org/cl/5754060

$ go run
go run: no go files listed
$ go run ../../pkg/math/bits.go
go run: cannot run non-main package
$

Fixes #3168.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5755064

R=rsc
CC=golang-dev
https://golang.org/cl/5753054

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5757050

The last CL forgot the all-important 'backdoor' package.
Cgo-using packages compile .c files with gcc, but we want
to compile this one with 6c, so put it in a non-cgo package.

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/5758063

By default the all.bash tests must not ever announce
on an external address.  It's not just an OS X issue.

R=golang-dev, mikioh.mikioh
CC=golang-dev
https://golang.org/cl/5753067

About 10% for hello, world.
Maybe more reductions will come.
Also clarify that we're comparing printf against Printf
(gcc can optimize aggressively, making this a different
sort of comparison).

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5756070

The testso directory still needs to be enabled.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5731048

$ go list -f '{{.ImportPath}} {{.Deps}}' fmt log
fmt [errors io math os reflect runtime strconv sync sync/atomic syscall time unicode/utf8 unsafe]
log [errors fmt io math os reflect runtime strconv sync sync/atomic syscall time unicode/utf8 unsafe]

R=bradfitz, rogpeppe, r, r, rsc
CC=golang-dev
https://golang.org/cl/5753055

We can write syslist.go by hand.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5757057

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5752066

R=golang-dev, bradfitz, alex.brainman
CC=golang-dev
https://golang.org/cl/5757058

There are a few more but these are the easiest ones.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5756067

We need a compact, reasonably efficient IsPrint. That adds about 2K of data,
plus a modest amount of code, but now strconv is a near-leaf package.

R=r, bradfitz, adg, rsc, minux.ma
CC=golang-dev
https://golang.org/cl/5756050

R=bradfitz
CC=golang-dev
https://golang.org/cl/5753066

Fixes #95.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5756066

R=r
CC=golang-dev
https://golang.org/cl/5752065