Fixes #6988.

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/44070046

Needed for precise gc and copying stacks.

reflect.Value now takes 4 words instead of 3.

Still to do:
 - un-iword-ify channel ops.
 - un-iword-ify method receivers.

R=golang-dev, iant, rsc, khr
CC=golang-dev
https://golang.org/cl/43040043

This makes the linker's -X flag work again.

R=iant
CC=bradfitz, golang-codereviews, golang-dev
https://golang.org/cl/44360043

Notably, to show allocs. Currently: 11766 B/op, 21 allocs/op,
at least one alloc of which is in the benchmark loop itself.

R=golang-dev, jnewlin
CC=golang-dev
https://golang.org/cl/40370057

The runtime tests are executed 4 times in all.bash
and there is currently a 5-second delay each time.

R=golang-dev, minux.ma, khr, bradfitz
CC=golang-dev
https://golang.org/cl/42450043

R=golang-dev, lucio.dere, rsc
CC=golang-dev
https://golang.org/cl/44080046

The code is all about tags, and the cmd/go documentation
said to look in the go/build documentation for information
about tags, but the documentation said nothing about tags,
only build constraints. Make things clearer.

R=golang-dev, adg, rsc
CC=golang-dev
https://golang.org/cl/44100043

Since SHA-256 is now the default hash function, x509 should import it
otherwise some programs may fail because it hasn't been linked in.

R=golang-dev, dave, minux.ma
CC=golang-dev
https://golang.org/cl/44010047

1. expr append executable extension.
2. support '\r' character.

Fixes #6851.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/35330043

Make hostobj work on OpenBSD 5.3/5.4/-current - these have PIE
enabled by default and linking fails since the Go linker generates
objects that are neither PIC nor PIE.

Fixes #5067

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7572049

To make it possible to type "go test -run=DNS".
Also removes unnecessary parens.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/43470051

Fixes #6338

R=golang-dev, kin.wilson.za, rsc
CC=golang-dev
https://golang.org/cl/36180044

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/44180043

We did this elsewhere when io.ByteReader was added
but forgot this one.

R=golang-dev, khr
CC=golang-dev
https://golang.org/cl/43480052

On the plus side, we don't need to change the bits when mallocing
pointerless objects.  On the other hand, we need to mark objects in the
free lists during GC.  But the free lists are small at GC time, so it
should be a net win.

benchmark                    old ns/op    new ns/op    delta
BenchmarkMalloc8                    40           33  -17.65%
BenchmarkMalloc16                   45           38  -15.72%
BenchmarkMallocTypeInfo8            58           59   +0.85%
BenchmarkMallocTypeInfo16           63           64   +1.10%

R=golang-dev, rsc, dvyukov
CC=cshapiro, golang-dev
https://golang.org/cl/41040043

Also removes an unused variable.

Fixes #6795.

R=adg, dave, bradfitz, gobot
CC=golang-dev
https://golang.org/cl/29440043

For machines, not threads.

Update #4720

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/44150043

Overloading size leads to problems if clients
try to set up an LSym by hand.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/44140043

R=r, bradfitz
CC=golang-dev
https://golang.org/cl/43480049

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/43480050

Update #4720

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/44080043

Benchmark is within the noise. I had to run this a dozen times
each before & after (on wall power, without a browser running)
before I could get halfway consistent numbers, and even then
they jumped all over the place, with the new one sometimes
being better. But these are the best of a dozen each.

Slowdown is expected anyway, since I imagine channels are
optimized more.

benchmark                 old ns/op    new ns/op    delta
BenchmarkCodeEncoder       26556987     27291072   +2.76%
BenchmarkEncoderEncode         1069         1071   +0.19%

benchmark                  old MB/s     new MB/s  speedup
BenchmarkCodeEncoder          73.07        71.10    0.97x

benchmark                old allocs   new allocs    delta
BenchmarkEncoderEncode            2            2    0.00%

benchmark                 old bytes    new bytes    delta
BenchmarkEncoderEncode          221          221    0.00%

Update #4720

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/37720047

Address several warnings generated by clang -fsanitize=undefined

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/43050043

Fixes #6576.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/14502065

Update #4078

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/14638043

sequences.

Use the same criteria for when to modify the tag type when
parsing a string in a sequence as when parsing a bare string
field.

Fixes #6726.

R=golang-dev, bradfitz, gobot, agl
CC=golang-dev
https://golang.org/cl/22460043

Float32 and Float64 are now both created by taking the ratio
of two integers which are chosen to fit entirely into the
precision of the desired float type. The previous code
could cast a Float64 with more than 23 bits of ".99999"
into a Float32 of 1.0, which is not in [0,1).

Float32 went from 15 to 21 ns/op (but is now correct).

Fixes #6721.

R=golang-dev, iant, rsc
CC=golang-dev
https://golang.org/cl/22730043

R=golang-dev, adg, rsc
CC=golang-dev
https://golang.org/cl/36950043

Fixes #6441.

R=r
CC=andybons, golang-dev
https://golang.org/cl/13829043

warning: src/cmd/6g/reg.c:671 format mismatch d VLONG, arg 4
warning: src/cmd/gc/pgen.c:230 set and not used: oldstksize
warning: src/cmd/gc/plive.c:877 format mismatch lx UVLONG, arg 2
warning: src/cmd/gc/walk.c:2878 set and not used: cbv
warning: src/cmd/gc/walk.c:2885 set and not used: hbv
warning: src/cmd/ld/data.c:198 format mismatch s IND FUNC(IND CHAR) INT, arg 2
warning: src/cmd/ld/data.c:230 format mismatch s IND FUNC(IND CHAR) INT, arg 2
warning: src/cmd/ld/dwarf.c:1517 set and not used: pc
warning: src/cmd/ld/elf.c:1507 format mismatch d VLONG, arg 2
warning: src/cmd/ld/ldmacho.c:509 set and not used: dsymtab

R=golang-dev, gobot, rsc
CC=golang-dev
https://golang.org/cl/36740045

warning: src/libmach/sym.c:1861 non-interruptable temporary
warning: src/cmd/8l/../ld/pcln.c:29 set and not used: p

R=golang-dev, gobot, rsc
CC=golang-dev
https://golang.org/cl/40500043

warning: src/liblink/asm5.c:485 non-interruptable temporary
warning: src/liblink/asm5.c:565 set and not used: c
warning: src/liblink/asm5.c:622 format mismatch ux VLONG, arg 2
warning: src/liblink/asm5.c:1218 overspecified class: asmout GLOBL STATIC
warning: src/liblink/asm5.c:2088 overspecified class: oprrr GLOBL STATIC
warning: src/liblink/asm5.c:2202 overspecified class: opbra GLOBL STATIC
warning: src/liblink/asm5.c:2237 overspecified class: olr GLOBL STATIC
warning: src/liblink/asm5.c:2266 overspecified class: olhr GLOBL STATIC
warning: src/liblink/asm5.c:2291 overspecified class: osr GLOBL STATIC
warning: src/liblink/asm5.c:2302 overspecified class: oshr GLOBL STATIC
warning: src/liblink/asm5.c:2312 overspecified class: osrr GLOBL STATIC
warning: src/liblink/asm5.c:2319 overspecified class: oshrr GLOBL STATIC
warning: src/liblink/asm5.c:2325 overspecified class: olrr GLOBL STATIC
warning: src/liblink/asm5.c:2332 overspecified class: olhrr GLOBL STATIC
warning: src/liblink/asm5.c:2338 overspecified class: ofsr GLOBL STATIC
warning: src/liblink/asm5.c:2375 overspecified class: omvl GLOBL STATIC
warning: src/liblink/asm8.c:1261 format mismatch d VLONG, arg 3
warning: src/liblink/asm8.c:1274 format mismatch +d VLONG, arg 5
warning: src/liblink/list5.c:153 format mismatch d VLONG, arg 3
warning: src/liblink/list5.c:310 format mismatch d VLONG, arg 3
warning: src/liblink/obj6.c:665 set and not used: q
warning: src/liblink/pcln.c:32 set and not used: p

R=golang-dev, jas, gobot, rsc
CC=golang-dev
https://golang.org/cl/40370043

Update #4720

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/43990043

Adds the Pool type and docs, and use it in fmt.
This is a temporary implementation, until Dmitry
makes it fast.

Uses the API proposal from Russ in http://goo.gl/cCKeb2 but
adds an optional New field, as used in fmt and elsewhere.
Almost all callers want that.

Update #4720

R=golang-dev, rsc, cshapiro, iant, r, dvyukov, khr
CC=golang-dev
https://golang.org/cl/41860043

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/43490048

This restores the old behaviour, and makes it possible to
continue to use 6g and 6l directly, rather than the go tool,
with dot imports.

R=rsc
CC=golang-dev
https://golang.org/cl/43710043

I forgot to apply Ian's suggestions before submitting CL 40600043.

R=iant
CC=golang-dev
https://golang.org/cl/43560045

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/37720046

R=golang-dev, gobot, bradfitz
CC=golang-dev
https://golang.org/cl/40810044

encoding/asn1: add more test cases for BitString.At and TestUTCTime, add test for ObjectIdentifier.Equal

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/42740043