Reduces number of write+seek's from 88516 to 2080
when linking godoc with 6l.

Thanks to Alex Brainman for pointing out the
many small writes.

R=golang-dev, r, alex.brainman, robert.hencke
CC=golang-dev
https://golang.org/cl/4743043

R=rsc, agl, mikioh.mikioh
CC=golang-dev
https://golang.org/cl/4667066

Add mutex to protect brk limit.
Add mstats.sys update.

R=rsc
CC=golang-dev
https://golang.org/cl/4762045

This affected certain signatures needing padding
like:

//export Foo
func Foo() (int, C.long) { ... }

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4745047

Fixes #2076.

R=golang-dev, r, r, dsymonds, lucio.dere
CC=golang-dev
https://golang.org/cl/4744047

interface field can be unpacked. We don't have type assertions here so we
must be forthright.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4757047

See /doc/codewalk/sharemem/ for an example of how it's broken.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4742044

- Clean and IsAbs to handle paths with drive letter properly.
- Clean to replace / with \.

R=golang-dev, adg
CC=golang-dev, mattn.jp
https://golang.org/cl/4758051

I suspect that this was introduced by
http://code.google.com/p/go/source/detail?r=6e4ee32fffd1

R=r
CC=golang-dev
https://golang.org/cl/4764045

R=r
CC=golang-dev
https://golang.org/cl/4756047

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4758050

Makes the code agree with the documentation.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/4759050

The story is more complicated; this is just a bandaid.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4755047

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4754050

It took it as an octal base prefix but assumed more digits were coming.
Fixes #2077.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/4764044

R=golang-dev, r
CC=golang-dev, rsc
https://golang.org/cl/4755046

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4754044

This didn't actually cause a bug, but looks wrong.

There was a lock but there was more shared mutable state not
guarded by it.

R=golang-dev, dsymonds, r
CC=golang-dev
https://golang.org/cl/4760047

The previous CL doicumented and diagnosed the old situation.
This one changes it to something more traditional: any action
may declare a variable, and the block structure of scopes
applies only to control seequences.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/4748047

In simple pipelines the declaration has no scope.
Also document the scope.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/4761044

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/4753044

6a/a.h:
. Dropped <u.h> and <libc.h>.
. Made definition of EOF conditional.

6a/a.y:
. Added <u.h> and <libc.h>.

6a/lex.c:
. Added <u.h> and <libc.h>.
. Dropped <ctype.h> (now in <u.h>).

6c/gc.h:
. Added varargck pragma for "lD".

6c/swt.c:
. Dropped unused "thestring" argument in Bprint() calls.

6l/Makefile:
. Dropped unneeded directory prefix.

6l/l.h:
. Dropped unneeded directory prefix.
. Added varargck pragma for "I" and "i".

6l/obj.c:
. Dropped unneeded assignment.
. Dropped unreachable goto statement.

6l/pass.c:
. Dropped assignments flagged as unused.

6l/prof.c:
. Replaced "#if 0" with "#ifdef NOTDEF".

6l/span.c:
. Dropped unused incrementation.
. Added USED() as required.
. Dropped unreachable "return" statement.

R=golang-dev
CC=golang-dev, rsc
https://golang.org/cl/4747044

5a/a.h:
. Removed <u.h> and <lib.h>.
. Made definition of EOF conditional.

5a/a.y:
. Added <u.h> and <lib.h>.

5a/lex.c:
. Added <u.h> and <lib.h>.
. Dropped <ctype.h> (now in <u.h>).

5c/peep.c:
. Removed unnecessary "return 0" statement.

5c/reg.c:
. Added compilation condition around unused code.

5c/swt.c:
. Removed unused "thestring" argument from Bprint() calls.

5l/asm.c:
. Added USED() statements as required.
. Adjusted a few format specifications.
. Added compilation condition around unused code.

5l/l.h:
. Dropped directory prefix from <../5l/5.out.h>.
. Added varargck pragma for "I" and "i".

5l/obj.c:
. Cascaded consecutive "if" statements.
. Dropped unnecessary incrementation and assignments.

5l/pass.c:
. Dropped unnecessary assignment.

5l/prof.c:
. #if 0 converted to #ifdef NOTDEF.

5l/span.c:
. Dropped unnecessary incrementation and assignments.

R=golang-dev
CC=golang-dev, rsc
https://golang.org/cl/4752041

8l/Makefile:
. Dropped unnecessary prefix from "../8l/8.out.h"

8l/l.h:
. Dropped unnecessary prefix from "../8l/8.out.h"
. Dropped unused and inconsistent "I" vararg pragma.

R=golang-dev
CC=golang-dev, rsc
https://golang.org/cl/4754041

benchmark                          old ns/op    new ns/op    delta
BenchmarkSemaUncontended               37.40        34.10   -8.82%
BenchmarkSemaUncontended-2             18.90        17.70   -6.35%
BenchmarkSemaUncontended-4             11.90        10.90   -8.40%
BenchmarkSemaUncontended-8              6.26         5.19  -17.09%
BenchmarkSemaUncontended-16             4.39         3.91  -10.93%
BenchmarkSemaSyntNonblock              38.00        35.30   -7.11%
BenchmarkSemaSyntNonblock-2            83.00        46.70  -43.73%
BenchmarkSemaSyntNonblock-4           124.00       101.00  -18.55%
BenchmarkSemaSyntNonblock-8           124.00       116.00   -6.45%
BenchmarkSemaSyntNonblock-16          148.00       114.00  -22.97%

(on HP Z600 2 x Xeon E5620, 8 HT cores, 2.40GHz)

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4755041

R=rsc
CC=golang-dev
https://golang.org/cl/4710046

R=dsymonds
CC=golang-dev
https://golang.org/cl/4746041

R=golang-dev, rsc, dsymonds
CC=golang-dev
https://golang.org/cl/4743041

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4714045

Previously, during the anti-zombie test, a
CGI process had to finish within ~625ms.
Now it gets ~5.6 seconds.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4741041

No formatting changes.

R=rsc
CC=golang-dev
https://golang.org/cl/4735042

R=rsc, bradfitz, r
CC=golang-dev
https://golang.org/cl/4738042

manual changes in src/pkg/go/printer, src/cmd/gofix/signal_test.go
(cd src/cmd/gofix/testdata; gofmt -w *.in *.out)
(cd src/pkg/go/printer; gotest -update)
gofmt -w misc src

runs all tests

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4715041

R=gri, ken, r
CC=golang-dev
https://golang.org/cl/4721044

Fixes #2032

R=rsc, dsymonds, r, r
CC=golang-dev
https://golang.org/cl/4709044

R=bradfitz
CC=golang-dev
https://golang.org/cl/4733041

Instead of serving files of the underlying OS file system,
a .zip file may be provided to godoc containing the files
to serve; for instance:

   godoc -http=:6060 -zip=go.zip

using a .zip file created from a clean tree as follows:

   zip -r go.zip $GOROOT

R=rsc
CC=golang-dev
https://golang.org/cl/4670053

Fixes #2056.

R=rsc
CC=golang-dev
https://golang.org/cl/4709042

Angle brackets can trigger some browser sniffers, causing
some forms of JSON output to be interpreted as HTML.
Escaping angle brackets closes that security hole.

R=rsc
CC=golang-dev
https://golang.org/cl/4701047

        {{range $key, $element := pipeline}}
This CL is smaller than it looks due to some rearrangement and renaming.

R=rsc, r
CC=golang-dev
https://golang.org/cl/4709047