Accomplished by synchronizing the formatting of conversion errors between typecheck.c and subr.c

Fixes #3984.

R=golang-dev, remyoudompheng, rsc
CC=golang-dev
https://golang.org/cl/6500064

Fixes #3909.
Fixes #3910.

R=rsc, nigeltao
CC=golang-dev
https://golang.org/cl/6442114

There was mail on golang-nuts a few weeks ago
from someone who understood the message perfectly
and knew he had a cyclic dependency but assumed
that Go, like Python or Java, was supposed to handle it.

R=golang-dev, bradfitz, dave
CC=golang-dev
https://golang.org/cl/6488069

The performance improvement applies to the case where
prec >= 0 and fmt is 'e' or 'g'.

Additional minor optimisations are included. A small
performance impact happens in some cases due to code
refactoring.

benchmark                              old ns/op    new ns/op    delta
BenchmarkAppendFloat64Fixed1                 623          235  -62.28%
BenchmarkAppendFloat64Fixed2                1050          272  -74.10%
BenchmarkAppendFloat64Fixed3                3723          243  -93.47%
BenchmarkAppendFloat64Fixed4               10285          274  -97.34%

BenchmarkAppendFloatDecimal                  190          206   +8.42%
BenchmarkAppendFloat                         387          377   -2.58%
BenchmarkAppendFloatExp                      397          339  -14.61%
BenchmarkAppendFloatNegExp                   377          336  -10.88%
BenchmarkAppendFloatBig                      546          482  -11.72%

BenchmarkAppendFloat32Integer                188          204   +8.51%
BenchmarkAppendFloat32ExactFraction          329          298   -9.42%
BenchmarkAppendFloat32Point                  400          372   -7.00%
BenchmarkAppendFloat32Exp                    369          306  -17.07%
BenchmarkAppendFloat32NegExp                 372          305  -18.01%

R=golang-dev, rsc
CC=golang-dev, remy
https://golang.org/cl/6462049

for both locale-specific exemplar characters and tailorings to
the collation table.
Some specifices:
- Moved stringSet to the beginning of the file and added some functionality
  to parse command line files.
- openReader now modifies the input URL for localFiles to guarantee that
  any http source listed in the generated file is indeed this source.
- Note that the implementation of the Tailoring API used by maketables.go
  is not yet checked in. So for now adding tailorings are simply no-ops.
- The generated file of exemplar characters will be used somewhere else.
  Here is a snippet of how the body of the generated file looks like:

type exemplarType int
const (
        exCharacters exemplarType = iota
        exContractions
        exPunctuation
        exAuxiliary
        exCurrency
        exIndex
        exN
)

var exemplarCharacters = map[string][exN]string{
        "af": [exN]string{
                0: "a á â b c d e é è ê ë f g h i î ï j k l m n o ô ö p q r s t u û v w x y z",
                3: "á à â ä ã æ ç é è ê ë í ì î ï ó ò ô ö ú ù û ü ý",
                4: "a b c d e f g h i j k l m n o p q r s t u v w x y z",
        },
        ...
}

R=r
CC=golang-dev
https://golang.org/cl/6501070

- Elements in the array are now sorted as a linked list.  This makes it easier to
  apply tailorings.
- Added code to sort entries by collation elements.
- Added logical reset points.  This is used for tailoring relative to certain
  properties, rather than characters.

NOTE: all code for type entry should now be in order.go.  To keep the diffs for
this CL reasonable, though, the existing code is left in builder.go.  I'll move
this in a separate CL.

R=r
CC=golang-dev
https://golang.org/cl/6493063

Fixes #3525.

PTRACE_SYSCALL behaves like PTRACE_CONT and can deliver
a signal to the process. Ideally PtraceSingleStep should
support the signal argument, but its interface is frozen
by Go1.

R=golang-dev, r, rsc
CC=golang-dev
https://golang.org/cl/6353051

TBR=r
CC=golang-dev
https://golang.org/cl/6497067

Parses a time header value into a time.Time according to rfc2616 sec 3.3.

R=golang-dev, dave, rsc, r
CC=bradfitz, golang-dev
https://golang.org/cl/6344046

R=rsc, n13m3y3r
CC=golang-dev
https://golang.org/cl/6330061

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/6492067

R=iant, imkrasin, krasin, iant, minux.ma, rsc, nigeltao, r, fullung
CC=golang-dev
https://golang.org/cl/6454046

Fixes #3975.

R=rsc, lvd
CC=golang-dev, remy
https://golang.org/cl/6475061

A crash happens in the first request in a connection
if "params" field is missing because c.req.Params is Nil.

Fixes #3848.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6446051

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/6497066

Reverts part of CL 6460082.

If a doc comment describes a type by explaining the
meaning of one instance of the type, a leading article
is fine and makes the text less awkward.

Compare:
// A dog is a kind of animal.
// Dog is a kind of animal.

R=golang-dev, dsymonds, dvyukov, r
CC=golang-dev
https://golang.org/cl/6494066

This set of changes extends the Plan 9 support
to include the AMD64 architecture and should
work on all versions of Plan 9.

R=golang-dev, rminnich, noah.evans, rsc, minux.ma, npe
CC=akskuma, golang-dev, jfflore, noah.evans
https://golang.org/cl/6479052

This fixes a spurious 'invalid recursive type' error, and stops the compiler from emitting errors on uses of the invalid type.

Fixes #3766.

R=golang-dev, dave, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6443100

The Handler method makes the ServeMux dispatch logic
available to wrappers that enforce additional constraints
on requests.

R=golang-dev, bradfitz, dsymonds
CC=golang-dev
https://golang.org/cl/6450165

In serve mux, if pattern contains a host name, pass only the path to
the redirect handler.

Add tests for serve mux redirections.

R=rsc
CC=bradfitz, gobot, golang-dev
https://golang.org/cl/6329045

Fixes #4008.

Run a background goroutine that wastes CPU to trick the
power management into raising the CPU frequency which,
by side effect, makes sleep more accurate on arm.

=== RUN TestParallelSleep
--- PASS: TestParallelSleep (1.30 seconds)
_cgo_gotypes.go:772:    sleep(1) slept for 1.000458s

R=minux.ma, r
CC=golang-dev
https://golang.org/cl/6498060

R=adg, bradfitz
CC=golang-dev
https://golang.org/cl/6490063

Also rename Node.{Add,Remove} to Node.{AppendChild,RemoveChild} to
be consistent with the DOM.

benchmark                      old ns/op    new ns/op    delta
BenchmarkParser                  4042040      3749618   -7.23%

benchmark                       old MB/s     new MB/s  speedup
BenchmarkParser                    19.34        20.85    1.08x

BenchmarkParser mallocs per iteration is also:
10495 before / 7992 after

R=andybalholm, r, adg
CC=golang-dev
https://golang.org/cl/6495061

R=r
CC=golang-dev
https://golang.org/cl/6489059

This is required by the spec to produce the replacement char.
The fix lies in lib9's rune code.

R=golang-dev, nigeltao, rsc
CC=golang-dev
https://golang.org/cl/6443109

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/6495059

R=r, r
CC=golang-dev
https://golang.org/cl/6494044

Other than catching an error case that was missed before, this
CL introduces no changes to the template language or API.

For simplicity, templates use spaces as argument separators.
This means that spaces are significant: .x .y is not the same as .x.y.
In the existing code, these cases are discriminated by the lexer,
but that means for instance that (a b).x cannot be distinguished
from (a b) .x, which is lousy. Although that syntax is not
supported yet, we want to support it and this CL is a necessary
step.

This CL emits a "space" token (actually a run of spaces) from
the lexer so the parser can discriminate these cases. It therefore
fixes a couple of undisclosed bugs ("hi".x is now an error) but
doesn't otherwise change the language. Later CLs will amend
the grammar to make .X a proper operator.

There is one unpleasantness: With space a token, three-token
lookahead is now required when parsing variable declarations
to discriminate them from plain variable references. Otherwise
the change isn't bad.

The CL also moves the debugging print code out of the lexer
into the test, which is the only place it's needed or useful.

Step towards resolving issue 3999.
It still remains to move field chaining out of the lexer
and into the parser and make field access an operator.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/6492054

No changes to the meaning, just clearer language and more
examples, including illegal rune and string literals.
In particular, "character literal" and "character constant"
are now called "rune literal" and "rune constant" and the
word "character" always refers to the source text, not
program values.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/6448137

        In the example "units" program for goyacc, the exchange rates were
        reciprocals of the correct amounts. Turn them right-side-up
        and update them to current figures.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/6495053

        Fixes #1635.

R=golang-dev, dave, r
CC=golang-dev
https://golang.org/cl/6496043

   while we are at it, fix some out-of-date comments.

R=golang-dev, dave, r
CC=golang-dev
https://golang.org/cl/6498054

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/6489049

Fixes #3892.

Swapping the order of the writers inside the MultiWriter ensures
the request will be written to buf before http.ReadRequest completes.

The fencedBuffer is not required to make the test pass on
any machine that I have access too, but as the buf is shared
across goroutines, I think it is necessary for correctness.

R=bradfitz, fullung, franciscossouza
CC=golang-dev
https://golang.org/cl/6483061

Also fix a bug in the script (s/runonly/run/)

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/6501051

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/6499043

benchmark             old ns/op    new ns/op    delta
BenchmarkAddVW_1              8            8   +0.60%
BenchmarkAddVW_2             10            9   -8.64%
BenchmarkAddVW_3             10           10   -4.63%
BenchmarkAddVW_4             10           11   +3.67%
BenchmarkAddVW_5             11           12   +5.98%
BenchmarkAddVW_1e1           18           20   +6.38%
BenchmarkAddVW_1e2          129          115  -10.85%
BenchmarkAddVW_1e3         1270         1089  -14.25%
BenchmarkAddVW_1e4        13376        12145   -9.20%
BenchmarkAddVW_1e5       130392       125260   -3.94%

benchmark              old MB/s     new MB/s  speedup
BenchmarkAddVW_1        7709.10      7661.92    0.99x
BenchmarkAddVW_2       12451.10     13604.00    1.09x
BenchmarkAddVW_3       17727.81     18721.54    1.06x
BenchmarkAddVW_4       23552.64     22708.81    0.96x
BenchmarkAddVW_5       27411.40     25816.22    0.94x
BenchmarkAddVW_1e1     34063.19     32023.06    0.94x
BenchmarkAddVW_1e2     49529.97     55360.55    1.12x
BenchmarkAddVW_1e3     50380.44     58764.18    1.17x
BenchmarkAddVW_1e4     47843.59     52696.10    1.10x
BenchmarkAddVW_1e5     49082.60     51093.66    1.04x

R=gri, rsc, r
CC=golang-dev
https://golang.org/cl/6480063

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/6476066

    Vim autocompletion respects the $GOPATH variable and does not
    ignore dashes ('-'), dots ('.') and underscores ('_') like found
    in many remote packages.
    Environment variable $GOROOT is determined by calling
    'go env GOROOT' instead of relying on the user's environment
    variables.

    Fixes #3876
    Fixes #3882

R=golang-dev, franciscossouza, dsymonds, minux.ma
CC=golang-dev
https://golang.org/cl/6443151

R=golang-dev, tobias.columbus, bradfitz
CC=golang-dev
https://golang.org/cl/6483058