Since we can't properly handle anything except 100, treat all
1xx informational responses as sketchy and don't reuse the
connection for future requests.

The only other 1xx response code currently in use in the wild
is WebSockets' use of "101 Switching Protocols", but our
code.google.com/p/go.net/websockets doesn't use Client or
Transport: it uses ReadResponse directly, so is unaffected by
this CL.  (and its tests still pass)

So this CL is entirely just future-proofing paranoia.
Also: the Internet is weird.

Update #2184
Update #3665

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/8208043

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8201043

Whoops. I'm surprised it even worked before. (Need two pipes,
not one.)

Also, remove the whole pipe registration business, since it
wasn't even required in the previous version. (I'd later fixed
it at the end of send100Response, but forgot to delete it)

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8191044

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8198043

R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/8187045

Some packages, like popwin.el, change display behaviour based on
the buffer's mode, so we should enable compilation-mode before
displaying the buffer.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8155043

src/cmd/gc/closure.c:133 param declared and not used: nowrap
src/cmd/gc/const.c:1139 set and not used: t1
src/cmd/ld/data.c:652 format mismatch #llx INT, arg 7
src/cmd/ld/data.c:652 format mismatch #llx INT, arg 8
src/cmd/ld/data.c:1230 set and not used: datsize

R=dave, golang-dev, lucio.dere, remyoudompheng, bradfitz
CC=golang-dev
https://golang.org/cl/8182043

src/cmd/6g/peep.c:471 set and not used: r
src/cmd/6g/peep.c:560 overspecified class: regconsttyp GLOBL STATIC
src/cmd/6g/peep.c:761 more arguments than format IND STRUCT Prog
src/cmd/6g/reg.c:185 set and not used: r1
src/cmd/6g/reg.c:786 format mismatch d VLONG, arg 3
src/cmd/6g/reg.c:1064 format mismatch d VLONG, arg 5

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8197044

R=golang-dev, bradfitz, minux.ma
CC=golang-dev
https://golang.org/cl/8193043

Add missing getgoextlinkenabled(void) declaration
in Plan 9 libc.h. This function was added as part
of CL #8183043.

R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/8191043

R=golang-dev, minux
CC=golang-dev
https://golang.org/cl/8174045

This CL ensures we use the correct socket options for
passive and active open sockets.

For the passive open sockets created by Listen functions,
additional SO_REUSEADDR, SO_REUSEPORT options are required
for the quick service restart and/or multicasting.

For the active open sockets created by Dial functions, no
additional options are required.

R=golang-dev, dave, bradfitz, rsc
CC=golang-dev
https://golang.org/cl/7795050

R=dsymonds, mikioh.mikioh
CC=golang-dev
https://golang.org/cl/8094047

"There are only two hard problems in computer science:
cache invalidation, naming things, and off-by-one errors."

The HTTP server code already strips Expect: 100-continue on
requests, so httputil.ReverseProxy should be unaffected, but
some servers send unsolicited HTTP/1.1 100 Continue responses,
so we need to skip over them if they're seen to avoid getting
off-by-one on Transport requests/responses.

This does change the behavior of people who were using Client
or Transport directly and explicitly setting "Expect: 100-continue"
themselves, but it didn't work before anyway. Now instead of the
user code seeing a 100 response and then things blowing up, now
it basically works, except the Transport will still blast away
the full request body immediately.  That's the part that needs
to be finished to close this issue.

This is the safe quick fix.

Update #3665

R=golang-dev, dsymonds, dave, jgrahamc
CC=golang-dev
https://golang.org/cl/8166045

Change build system to set GO_EXTLINK_ENABLED=0 by default for
OS X 10.6, since the system linker has a bug and can not
handle the object files generated by 6l.

Fixes #5130.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8183043

This benchmark verifies that CL #8173043 reduces time spent
sliding the Buffer's contents.

Results without and with CL #8173043 applied:
benchmark                        old ns/op    new ns/op    delta
BenchmarkBufferFullSmallReads       755336       175054  -76.82%

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8174043

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/8176043

Do a little reformatting too.
Fixes #5152.

R=golang-dev, bradfitz, gri
CC=golang-dev
https://golang.org/cl/8157044

For the future.

Update #5147

R=khr, r
CC=golang-dev
https://golang.org/cl/8165044

benchmark                           old ns/op    new ns/op    delta
BenchmarkBufferNotEmptyWriteRead       848416       819983   -3.35%

Update #5154

R=golang-dev, gri, robryk
CC=golang-dev
https://golang.org/cl/8173043

Also added a new benchmark from the same test:

benchmark                           old ns/op    new ns/op    delta
BenchmarkBufferNotEmptyWriteRead      2643698       709189  -73.17%

Fixes #5154

R=golang-dev, r, gri
CC=golang-dev
https://golang.org/cl/8164043

Fixes #5098

R=minux.ma, bradfitz, khr, rsc
CC=golang-dev
https://golang.org/cl/7746045

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7548045

These only show up if GOTRACEBACK=2

Update #5005

R=golang-dev, fullung
CC=golang-dev
https://golang.org/cl/8156044

Used by CL 8056043 for fast string equals.

R=bradfitz
CC=golang-dev
https://golang.org/cl/8102044

Update #4234.
Update #4501.

R=golang-dev, dave, bradfitz
CC=golang-dev
https://golang.org/cl/8129043

R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/8073044

Adds the missing wildcard port assignment description to ListenUDP.
Also updates the wildcard port description on ListenTCP.

R=golang-dev, dave, r
CC=golang-dev
https://golang.org/cl/8063043

Closes the API documentation gap between platforms.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8086043

Also removes redundant tests that run Go 1.0 non-IPv6 support
Windows code on IPv6 enabled Windows kernels.

R=alex.brainman, golang-dev, bradfitz, dave
CC=golang-dev
https://golang.org/cl/7812052

Fixes #5005

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8127043

With the faster strings package, the difference between
the specialized code and strings.Split is in the noise:

benchmark         old ns/op    new ns/op    delta
BenchmarkPrint     16724291     16686729   -0.22%

(Measured on a Mac Pro, 2.8GHz Quad-core Intel Xeon,
4GB 800 MHz DDR2, Mac OS X 10.8.3)

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8100044

Fixes #5150.

R=golang-dev, franciscossouza
CC=golang-dev
https://golang.org/cl/8120043

Saves both the textproto.Reader allocation, and its internal
scratch buffer growing.

benchmark                                   old ns/op    new ns/op    delta
BenchmarkServerFakeConnWithKeepAliveLite        10324        10149   -1.70%

benchmark                                  old allocs   new allocs    delta
BenchmarkServerFakeConnWithKeepAliveLite           19           17  -10.53%

benchmark                                   old bytes    new bytes    delta
BenchmarkServerFakeConnWithKeepAliveLite         1559         1492   -4.30%

R=golang-dev, r, gri
CC=golang-dev
https://golang.org/cl/8094046

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8122043

Updates #5134

R=golang-dev, bradfitz, cshapiro, daniel.morsing, ality, iant
CC=golang-dev
https://golang.org/cl/8022044

Removes another per-request allocation. Also makes the code more
readable, IMO. And more testable.

benchmark                                   old ns/op    new ns/op    delta
BenchmarkServerFakeConnWithKeepAliveLite        10539        10324   -2.04%

benchmark                                  old allocs   new allocs    delta
BenchmarkServerFakeConnWithKeepAliveLite           20           19   -5.00%

benchmark                                   old bytes    new bytes    delta
BenchmarkServerFakeConnWithKeepAliveLite         1609         1559   -3.11%

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/8118044

We already depend on strings in this file, so use it.

Plus strings.Index will be faster than a manual loop
once issue 3751 is finished.

R=golang-dev, khr
CC=golang-dev
https://golang.org/cl/8116043

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8113043

A chunkWriter and a response are 1:1. Make them contiguous in
memory and save an allocation.

benchmark                                   old ns/op    new ns/op    delta
BenchmarkServerFakeConnWithKeepAliveLite        10715        10539   -1.64%

benchmark                                  old allocs   new allocs    delta
BenchmarkServerFakeConnWithKeepAliveLite           21           20   -4.76%

benchmark                                   old bytes    new bytes    delta
BenchmarkServerFakeConnWithKeepAliveLite         1626         1609   -1.05%

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/8114043