If reports like #13062 are really concurrent misuse of maps,
we can detect that, at least some of the time, with a cheap check.

There is an extra pair of memory writes for writing to a map,
but to the same cache line as h.count, which is often being modified anyway,
and there is an extra memory read for reading from a map,
but to the same cache line as h.count, which is always being read anyway.
So the check should be basically invisible and may help reduce the
number of "mysterious runtime crash due to map misuse" reports.

Change-Id: I0e71b0d92eaa3b7bef48bf41b0f5ab790092487e
Reviewed-on: https://go-review.googlesource.com/17501Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

The following code:

func n() {(interface{int})}

generates:

3: interface contains embedded non-interface int
3: type %!v(PANIC=runtime error: invalid memory address or nil pointer dereference) is not an expression

It is because the corresponding symbol (Sym field in Type object)
is nil, resulting in a panic in typefmt.

Just skip the symbol if it is nil, so that the error message becomes:

3: interface contains embedded non-interface int
3: type interface { int } is not an expression

Fixes #11614

Change-Id: I219ae7eb01edca264fad1d4a1bd261d026294b00
Reviewed-on: https://go-review.googlesource.com/14015Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>

algtype already controls the behavior of the normal map access code
paths, so it makes sense to base the decision on which optimized paths
are applicable on it too.

Enables use of optimized paths for key types like [8]byte and struct{s
string}.

Fixes #13271.

Change-Id: I48c52d97abaa7259ad5aba9641ea996a967cd359
Reviewed-on: https://go-review.googlesource.com/17464
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

Prior behavior would show empty string when unset. In go1.5 this
would result in "off". In go1.6 this will result in "on". This
change will make empty or "0" off and "1" on for go1.5 and go1.6.
Vendor tools can then rely on this value.

Discussion:
https://groups.google.com/forum/#!topic/golang-dev/oZzcXrlRrkA

Change-Id: I7e145a32e813dfde02dc262a9186c7af28db7b92
Reviewed-on: https://go-review.googlesource.com/17487Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: Ifa9f1ed6a3b8d3f7536f2d315259940335b0ee49
Reviewed-on: https://go-review.googlesource.com/17438Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I411aeaf0cf75eb8b1c9005b622f664e9f25e4a68
Reviewed-on: https://go-review.googlesource.com/17400Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #7991.
Fixes #12719.

Change-Id: I5650fa35ec5d49addeda6cc6e7fa93cfbe1cdfc0
Reviewed-on: https://go-review.googlesource.com/17385Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>

This change modifies comments to use the more gramatically correct "more than"
instead of "more then".

Change-Id: Ie3bddcf25eb6b243a21da934f2f3c76a750c083a
Reviewed-on: https://go-review.googlesource.com/17488Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I321eba716319bf88695ac49580837b6254f1279e
Reviewed-on: https://go-review.googlesource.com/17474Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

This is CL 11882 brought back to life.

Fixes #11551

Change-Id: I29810183957745442d1e9937f56a66fc9c6cc82a
Reviewed-on: https://go-review.googlesource.com/17470Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The build tags are necessary to keep "go build" in that directory
building only stdio.go, but we have to arrange for test/run.go to
treat them as satisfied.

Fixes #12625.

Change-Id: Iec0cb2fdc2c9b24a4e0530be25e940aa0cc9552e
Reviewed-on: https://go-review.googlesource.com/17454
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

(sig is unsigned, so sig-1 >= 0 is always true.)

Fixes #11281.

Change-Id: I4b9d784da6e3cc80816f2d2f7228d5d8a237e2d5
Reviewed-on: https://go-review.googlesource.com/17457Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #11609.

Change-Id: I3cf64164fde28ebf739706728b84d8ef5b6dc90e
Reviewed-on: https://go-review.googlesource.com/17456Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #11290.

Change-Id: I312f0731077b78a4bed47062eb7fd1ab52bc3dd1
Reviewed-on: https://go-review.googlesource.com/17453Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #12970.

Change-Id: Id0026e8274e071d65d47df63d65a93110abbec5d
Reviewed-on: https://go-review.googlesource.com/15998Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This reverts commit f25f6eab.

Sorry, this was not meant to go in without the ztypes_freebsd_arm.go and the copyFromV9 function.

Change-Id: I4ac2a8a23809ec1b1b9e42992cd0f3c349848f06
Reviewed-on: https://go-review.googlesource.com/17472
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This was a mistake made when bringing cmd/vet into the main repo.

Fixes #13416.

Change-Id: I03b512ab944577c56085aea06df8ff5e1acc16d7
Reviewed-on: https://go-review.googlesource.com/17455Reviewed-by: Matthew Dempsky <mdempsky@google.com>

This change makes existing Lookup API test cases conform to the new
return value form that all the Lookup APIs except LookupTXT must return
a single or multiple absolute domain names.

Updates #12189.
Fixes #12193.

Change-Id: I03ca09be5bff80e818fbcdc26039daa33d5440a8
Reviewed-on: https://go-review.googlesource.com/17411
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #13480.

Change-Id: Icbf4f83e965e84f7020f56c3f346193f8b91e7bf
Reviewed-on: https://go-review.googlesource.com/17461Reviewed-by: Russ Cox <rsc@golang.org>

Switch IfMsghdr and IfaMsghdr to their 'l' variants, make the IfData layout
to be based on FreeBSD-11.0 (freebsdVersion >= 1100011).
Using freebsdVersion, detect the appropriate layout at runtime and decode
routing socket messages into the new IfData layout.

Fixes #11641

Change-Id: Ic7ec550f00c0d15f46a36f560d835e4f138f61e1
Reviewed-on: https://go-review.googlesource.com/14757Reviewed-by: Russ Cox <rsc@golang.org>

Try to remove the most visible artefacts resulting from the
C to Go translation. It includes:

- refactoring the find function to eliminate goto and variable declarations
- removing useless variables still having a _ = xxx
- decreasing the number of upfront variable declarations

No semantic changes.

Change-Id: I84d981c48b2d9e22e6b9db5f2a703c80c60249ba
Reviewed-on: https://go-review.googlesource.com/15681Reviewed-by: Russ Cox <rsc@golang.org>

Set the status code in case of error.

Fixes #11510

Change-Id: If461c30a1f6d2275539f33a2eabd7b19bbfa411d
Reviewed-on: https://go-review.googlesource.com/16718Reviewed-by: Russ Cox <rsc@golang.org>

Prior to this change "go tool vet -all -shadow" ran only -shadow check.

Also fix godoc package path in the usage text.

Fixes #13020

Change-Id: I87c60d6b06a02106ae8bff56adb79df032cc4646
Reviewed-on: https://go-review.googlesource.com/16325Reviewed-by: Russ Cox <rsc@golang.org>

Simplify slice/map literal expression.
Caught with gofmt -d -s, fixed with gofmt -w -s

Change-Id: I19723900d0649019bf79b9330d68525a68ed69c4
Reviewed-on: https://go-review.googlesource.com/13835Reviewed-by: Russ Cox <rsc@golang.org>

Fixes #12200.

Change-Id: I89f2a7326bb9182024c44bf815a06fa48639649d
Reviewed-on: https://go-review.googlesource.com/17384Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

There is a report that fd 10 is already in use when run on some OS X machines.
I don't see how, and I can't reproduce the problem on my own OS X machine,
but it's easy enough to fix.

Fixes #12161.

Change-Id: I73511bdd91258ecda181d60d2829add746d1198b
Reviewed-on: https://go-review.googlesource.com/17451Reviewed-by: Ian Lance Taylor <iant@golang.org>

When run with "ulimit -s unlimited", the misc/cgo/test test binary
finds a stack size of 0x3000 returned by getcontext, causing the
runtime to try to stay within those bounds and then fault when
called back in the test after 64 kB has been used by C.

I suspect that Solaris is doing something clever like reporting the
current stack size and growing the stack as faults happen.
On all the other systems, getcontext reports the maximum stack size.
And when the ulimit is not unlimited, even Solaris reports the
maximum stack size.

Work around this by assuming that any stack on Solaris must be at least 1 MB.

Fixes #12210.

Change-Id: I0a6ed0afb8a8f50aa1b2486f32b4ae470ab47dbf
Reviewed-on: https://go-review.googlesource.com/17452Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: I3870150fc8e713f6164371299c029b31f18f250a
Reviewed-on: https://go-review.googlesource.com/17426Reviewed-by: Minux Ma <minux@golang.org>

Change-Id: Idfbe91abc11b2b3b735cd8d11fb1938f9e5c0473
Reviewed-on: https://go-review.googlesource.com/17437Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: Icad6cc130252ac177946b23c12f36d6ba3275bf0
Reviewed-on: https://go-review.googlesource.com/17436
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I69e62199140e5cf203696af17d4816f3a5f13bd1
Reviewed-on: https://go-review.googlesource.com/17434
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I4cf4596a305510cd25df34ecebd11a19266415f1
Reviewed-on: https://go-review.googlesource.com/17435
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Motivation:
* Previous implementation did not detect integer overflow when
parsing a base-256 encoded field.
* Previous implementation did not treat the integer as a two's
complement value as specified by GNU.

The relevant GNU specification says:
<<<
GNU format uses two's-complement base-256 notation to store values
that do not fit into standard ustar range.
>>>

Fixes #12435

Change-Id: I4639bcffac8d12e1cb040b76bd05c9d7bc6c23a8
Reviewed-on: https://go-review.googlesource.com/17424Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I77e4df7ab0bc20d2e251c1eda9ce9026484b8bbc
Reviewed-on: https://go-review.googlesource.com/17433Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Motivation:
* Previous implementation silently failed when an integer overflow
occurred. Now, we report an ErrFieldTooLong.
* Previous implementation did not encode in two's complement format and was
unable to encode negative numbers.

The relevant GNU specification says:
<<<
GNU format uses two's-complement base-256 notation to store values
that do not fit into standard ustar range.
>>>

Fixes #12436

Change-Id: I09c20602eabf8ae3a7e0db35b79440a64bfaf807
Reviewed-on: https://go-review.googlesource.com/17425Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Revert "Revert "sort: improve average quicksort performance""
This reverts commit 30b87bb9.

See https://golang.org/cl/15688 for the CL being replayed.

Change-Id: I2ba36334003f4971f95a10536adfdd86be9a50de
Reviewed-on: https://go-review.googlesource.com/17389
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

Currently only one blank line is checked to be removed.
Changing sort.Sort may lead to more blank lines.
Let's remove them all.

It fixes a bug found by https://golang.org/cl/15688

Change-Id: I682cc23ecd7b10d9b6feb160da040a155297f578
Reviewed-on: https://go-review.googlesource.com/17440
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

Change-Id: I009eaa52d03f1c3af33a6e884332f41c7cf48edd
Reviewed-on: https://go-review.googlesource.com/17427Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This is an example of converting an old HTTP/1-only test to test
against both HTTP/1 and HTTP/2.

Please send more of these!

Also, for comparing the http.Transport's responses between HTTP/1 and
HTTP/2, see clientserver_test.go's h12Compare type and tests using
h12Compare. Sometimes that's the more appropriate option.

Change-Id: Iea24d844481efd5849173b60e15dcc561a32b88f
Reviewed-on: https://go-review.googlesource.com/17409Reviewed-by: Burcu Dogan <jbd@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Broke the build: http://build.golang.org/log/8159de7e0d6f3832da394c310975ddd4c4c74627
(cmd/gofmt TestRewrite)

This reverts commit 6f6b2f04.

Change-Id: Ifd46b0b76c30b0a568521eaaf5ef8968a9549bf5
Reviewed-on: https://go-review.googlesource.com/17383Reviewed-by: Russ Cox <rsc@golang.org>