In another CL, I'll add a pure Go implementation of lookupGroup and
lookupGroupId in lookup_unix.go, but attempting that in one CL makes
the diff too difficult to read.

Updates #18102.

Change-Id: If8e26cee5efd30385763430f34304c70165aef32
Reviewed-on: https://go-review.googlesource.com/37497Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

That failing test is preventing other tests from running.
Let's see what else is broken.

Updates #19293

Change-Id: I4c5784be94103ef882f29dec9db08d76a48aff28
Reviewed-on: https://go-review.googlesource.com/37492
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matt Layher <mdlayher@gmail.com>

Measured on 2.3 GHz Intel Core i7, running macOS 10.12.3:

benchmark                old ns/op     new ns/op     delta
BenchmarkReverse8-8      1.70          0.99          -41.76%
BenchmarkReverse16-8     2.24          1.32          -41.07%

Fixes #19279.

Change-Id: I398cf8a3513b7fa63c130efc7846a7c5353999d4
Reviewed-on: https://go-review.googlesource.com/37459
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: Iae9fe2db69c02cd442cba01a78820dc7c0fdda51
Reviewed-on: https://go-review.googlesource.com/37462
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Follow-up to CL 37270.

This considerably reduces the time to run the test.

Before:

real	0m7.638s
user	0m14.341s
sys	0m2.244s

After:

real	0m4.867s
user	0m7.107s
sys	0m1.842s

Change-Id: I8837a5da0979a1c365e1ce5874d81708249a4129
Reviewed-on: https://go-review.googlesource.com/37461
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Munday <munday@ca.ibm.com>

Simple change to allow plugins for linux on s390x

Change-Id: I5c262ab81aac10d1dcb03381a48e5b9694b7a87a
Reviewed-on: https://go-review.googlesource.com/37451
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

New special case for booleans and byte-sized integer types
converted to interfaces needs to ensure that the operand is
not too complex, if it were to appear in a parameter list
for example.

Added test, also increased the recursive node dump depth to
a level that was actually useful for an actual bug.

Fixes #19275.

Change-Id: If36ac3115edf439e886703f32d149ee0a46eb2a5
Reviewed-on: https://go-review.googlesource.com/37470
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Change-Id: I3e40018ab1903d3b9ada7ad7812ba71ea2a428e7
Reviewed-on: https://go-review.googlesource.com/37456Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

name                  old time/op  new time/op  delta
ByteByteMap-4         2.03µs ± 2%  1.03µs ± 2%  -49.24%  (p=0.000 n=10+10)
Map/identity/ASCII-4   246ns ± 0%   158ns ± 0%  -35.90%    (p=0.000 n=9+9)
Map/identity/Greek-4   367ns ± 1%   273ns ± 1%  -25.63%  (p=0.000 n=10+10)
Map/change/ASCII-4     582ns ± 1%   324ns ± 1%  -44.34%  (p=0.000 n=10+10)
Map/change/Greek-4     709ns ± 2%   623ns ± 2%  -12.16%  (p=0.000 n=10+10)
MapNoChanges-4         171ns ± 1%   111ns ± 1%  -35.36%   (p=0.000 n=8+10)

Updates #17859

Change-Id: I55d7d261fdc1ce2dcd0ebe23b0fa20b9889bf54c
Reviewed-on: https://go-review.googlesource.com/33201Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The number of open file descriptors reported by lsof is unreliable
because it depends on whether the parent process (the test) closed
the file descriptors it passed into the child process (lsof) before
lsof runs.

Reading /proc/self/fd directly on Linux appears to be much more
reliable and still detects any file descriptor leaks originating
from attempting to run an executable that cannot be found (issue
#5071). If /proc/self/fd is not available (e.g. on Darwin) then we
fall back to lsof and tolerate small differences in open file
descriptor counts.

Fixes #19243.

Change-Id: I052b0c129e609010f1083e43a9911cba154117bf
Reviewed-on: https://go-review.googlesource.com/37343
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Add Set3 function to complement existing Set1 and Set2 functions.
Consistently use Set1, Set2 and Set3 for []*Node instead of Set where applicable.

Add SetFirst and SetSecond for setting elements of []*Node to mirror
First and Second for accessing elements in []*Node.

Replace uses of Index by First and Second and
SetIndex with SetFirst and SetSecond where applicable.

Passes toolstash -cmp.

Change-Id: I8255aae768cf245c8f93eec2e9efa05b8112b4e5
Reviewed-on: https://go-review.googlesource.com/37430
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

TestAssembly was very slow, leading to it being skipped by default.
This is not surprising, it separately invoked the compiler and
parsed the result many times.

Now the test assembles one source file for arch/os combination,
containing the relevant functions.

Tests for each arch/os run in parallel.

Now the test runs approximately 10x faster on my Intel(R) Core(TM)
i5-6600 CPU @ 3.30GHz.

Fixes #18966

Change-Id: I45ab97630b627a32e17900c109f790eb4c0e90d9
Reviewed-on: https://go-review.googlesource.com/37270
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This should help on the openbsd systems where the test mostly passes.

I don't expect it to help on s390x where the test reliably fails.
But it should give more information when it does fail.

For #19276.

Change-Id: I496c291f2b4b0c747b8dd4315477d87d03010059
Reviewed-on: https://go-review.googlesource.com/37348
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I3c31f10c1082c7bc57aac18856014c55f79e0fed
Reviewed-on: https://go-review.googlesource.com/37409Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The profiles are self-contained now.
Check that they work by themselves in the tests that invoke pprof,
but also keep checking that the old command lines work.

Change-Id: I24c74b5456f0b50473883c3640625c6612f72309
Reviewed-on: https://go-review.googlesource.com/37166
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>

Nothing needs internal/pprof anymore except the runtime/pprof tests.
Move the package here to prevent new dependencies.

Change-Id: Ia119af91cc2b980e0fa03a15f46f69d7f71d2926
Reviewed-on: https://go-review.googlesource.com/37165
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>

The existing code builds a full profile in memory.
Then it translates that profile into a data structure (in memory).
Then it marshals that data structure into a protocol buffer (in memory).
Then it gzips that marshaled form into the underlying writer.
So there are three copies of the full profile data in memory
at the same time before we're done. This is obviously dumb.

This CL implements a fully streaming conversion from
the original in-memory profile to the underlying writer.
There is now only one copy of the profile in memory.

For the non-CPU profiles, this is optimal, since we have to
have a full copy in memory to start with.

For the CPU profiles, we could still try to bound the profile
size stored in memory and stream fragments out during
the actual profiling, as Go 1.7 did (with a simpler format),
but so far that hasn't been necessary.

Change-Id: Ic36141021857791bf0cd1fce84178fb5e744b989
Reviewed-on: https://go-review.googlesource.com/37164
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>

This change adds math/bits as a new dependency of math/big.

- use bits.LeadingZeroes instead of local implementation
  (they are identical, so there's no performance loss here)

- leave other functionality local (ntz, bitLen) since there's
  faster implementations in math/big at the moment

Change-Id: I1218aa8a1df0cc9783583b090a4bb5a8a145c4a2
Reviewed-on: https://go-review.googlesource.com/37141Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Import the github.com/google/pprof and github.com/ianlancetaylor/demangle
packages, without modification.

Build the golang version of pprof from cmd/pprof/pprof.go
by importing the packages from src/cmd/vendot/github.com/google/pprof

The versions upstreamed are:

github.com/ianlancetaylor/demangle 4883227f66371e02c4948937d3e2be1664d9be38
github.com/google/pprof            7eb5ba977f28f2ad8dd5f6bb82cc9b454e123cdc

Update misc/nacl/testzip.proto for new tests.

Change-Id: I076584856491353607a3b98b67d0ca6838be50d6
Reviewed-on: https://go-review.googlesource.com/36798
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

Wait a short period between trying commands. Many commands
will return a non-zero exit code if the browser couldn't be launched.

For example, google-chrome returns quickly with a non-zero
exit code in a headless environment.

Updates #19131.

Change-Id: I0ae5356dd4447969d9e216615449cead7a8fd5c9
Reviewed-on: https://go-review.googlesource.com/37391Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

CL 35562 substituted zerobase for the pointer for
interfaces containing zero-sized values.
However, it failed to evaluate the zero-sized value
expression for side-effects. Fix that.

The other similar interface value optimizations
are not affected, because they all actually use the
value one way or another.

Fixes #19246

Change-Id: I1168a99561477c63c29751d5cd04cf81b5ea509d
Reviewed-on: https://go-review.googlesource.com/37395
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

The new syntax tree introduced with 1.8 represents send statements
(ch <- x) as statements; the old syntax tree represented them as
expressions (and parsed them as such) but complained if they were
used in expression context. As a consequence, some of the errors
that in the past were of the form "ch <- x used as value" now look
like "unexpected <- ..." because a "<-" is not valid according to
Go syntax in those situations. Accept the new error message.

Also: Fine-tune handling of misformed for loop headers.

Also: Minor cleanups/better comments.

Fixes #17590.

Change-Id: Ia541dea1f2f015c1b21f5b3ae44aacdec60a8aba
Reviewed-on: https://go-review.googlesource.com/37386Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Brings in chacha20poly1305 directory from golang.org/x/crypto revision
453249f01cfeb54c3d549ddb75ff152ca243f9d8, adding:

CL 35874: crypto/chacha20poly1305/internal/chacha20: add missing copyright header
CL 35875: crypto/chacha20poly1305: rename test vectors file

Fixes #19155.

Change-Id: I25cf83d060113f6b2a197f243a25614440008f7e
Reviewed-on: https://go-review.googlesource.com/37408Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Set $GOPATH to a semantically valid, non-empty string that cannot
conflict with $GOROOT to avoid false test failures that occur when
$GOROOT resides under $GOPATH.  Unsetting GOPATH is no longer viable
as Go now defines a default $GOPATH that may conflict with $GOROOT.

Fixes #19237

Change-Id: I376a2ad3b18e9c4098211b988dde7e76bc4725d2
Reviewed-on: https://go-review.googlesource.com/37396Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The old hash table was a place holder that allocates memory
during every lookup for key generation, even for keys that hit
in the the table.

Change-Id: I4f601bbfd349f0be76d6259a8989c9c17ccfac21
Reviewed-on: https://go-review.googlesource.com/37163
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>

This doesn't change the functionality of the current code,
but it sets us up for exporting the profiling labels into the profile.

The old code had a hash table of profile samples maintained
during the signal handler, with evictions going into a log.
The new code just logs every sample directly, leaving the
hash-based deduplication to an ordinary goroutine.

The new code also avoids storing the entire profile in two
forms in memory, an unfortunate regression introduced
when binary profile support was added. After this CL the
entire profile is only stored once in memory. We'd still like
to get back down to storing it zero times (streaming it to
the underlying io.Writer).

Change-Id: I0893a1788267c564aa1af17970d47377b2a43457
Reviewed-on: https://go-review.googlesource.com/36712
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>

It's common for some goroutines to loop calling time.Sleep.
Allocate once per goroutine, not every time.
This comes up in runtime/pprof's background reader.

Change-Id: I89d17dc7379dca266d2c9cd3aefc2382f5bdbade
Reviewed-on: https://go-review.googlesource.com/37162Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Some field-lists (especially in generated code) can be excessively long.
In the one-line printout, it does not make sense to print all elements
of the list if line-wrapping causes the "one-line" to become multi-line.

// Before:
var LongLine = newLongLine("someArgument1", "someArgument2", "someArgument3", "someArgument4", "someArgument5", "someArgument6", "someArgument7", "someArgument8")

// After:
var LongLine = newLongLine("someArgument1", "someArgument2", "someArgument3", "someArgument4", ...)

Change-Id: I4bbbe2dbd1d7be9f02d63431d213088c3dee332c
Reviewed-on: https://go-review.googlesource.com/36031
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

An io.Reader does not guarantee that it will read in the entire buffer.
To ensure that property, io.ReadFull should be used instead.

Change-Id: I0b863135ab9abc40e813f9dac07bfb2a76199950
Reviewed-on: https://go-review.googlesource.com/37403Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The loop-A-encloses-loop-C code did not properly handle the
case where really C was already known to be enclosed by B,
and A was nearest-outer to B, not C.

Fixes #19217.

Change-Id: I755dd768e823cb707abdc5302fed39c11cdb34d4
Reviewed-on: https://go-review.googlesource.com/37340
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

Fixes #19249.

Change-Id: I6327192eca11fa24f1078c016c9669e4ba4bdb4e
Reviewed-on: https://go-review.googlesource.com/37399Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Avoid printing a second error message when a field of an undefined
variable is accessed.

Fixes #8440.

Change-Id: I3fe0b11fa3423cec3871cb01b5951efa8ea7451a
Reviewed-on: https://go-review.googlesource.com/36751Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The existing CPU profiling buffer is a slice of uintptr, but we want to
start including profiling label data in the profiles, and those labels need
to be pointers in order to let them describe rich information.

This CL implements a new profBuf type that holds both a slice of uint64
for data and a slice of unsafe.Pointer for profiling labels (aka tags).
Making the runtime use these buffers will happen in followup CLs.

Change-Id: I9ff16b532d8edaf4ce0cbba1098229a561834efc
Reviewed-on: https://go-review.googlesource.com/36713
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Fixes #19253

Change-Id: Ia473f51bfe4cf42cf64938993a81d9b1dbc2594d
Reviewed-on: https://go-review.googlesource.com/37433Reviewed-by: Chris Broadfoot <cbro@golang.org>

xdg-open's man page says:
> xdg-open is for use inside a desktop session only.

Use the DISPLAY environment variable to detect this.

Updates #19131.

Change-Id: I3926b3e1042393939b2ec6aacd9b63ac8192df3b
Reviewed-on: https://go-review.googlesource.com/37390Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

When running on the host platform,
the standard library has almost certainly already been built.
However, all other platforms will probably need building.
Use the new -dolinkobj=false flag to cmd/compile
to only build the export data instead of doing a full compile.

Having partial object files could be confusing for people
doing subsequent cross-compiles, depending on what happens with #18369.
However, cmd/vet/all will mainly be run by builders
and core developers, who are probably fairly well-placed
to handle any such confusion.

This reduces the time on my machine for a cold run of
'go run main.go -all' by almost half:

benchmark           old ns/op        new ns/op        delta
BenchmarkVetAll     240670814551     130784517074     -45.66%

Change-Id: Ieb866ffb2cb714b361b0a6104077652f8eacd166
Reviewed-on: https://go-review.googlesource.com/37385
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

When set to false, the -dolinkobj flag instructs the compiler
not to generate or emit linker information.

This is handy when you need the compiler's export data,
e.g. for use with go/importer,
but you want to avoid the cost of full compilation.

This must be used with care, since the resulting
files are unusable for linking.

This CL interacts with #18369,
where adding gcflags and ldflags to buildid has been mooted.
On the one hand, adding gcflags would make safe use of this
flag easier, since if the full object files were needed,
a simple 'go install' would fix it.
On the other hand, this would mean that
'go install -gcflags=-dolinkobj=false' would rebuild the object files,
although any existing object files would probably suffice.

Change-Id: I8dc75ab5a40095c785c1a4d2260aeb63c4d10f73
Reviewed-on: https://go-review.googlesource.com/37384
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Fixes #19244

Change-Id: Ia6332941b229c83d6fd082af49f31003a66b90db
Reviewed-on: https://go-review.googlesource.com/37388Reviewed-by: Robert Griesemer <gri@golang.org>

Replaces pairs of shifts with sign/zero extension where possible.

For example:
(uint64(x) << 32) >> 32 -> uint64(uint32(x))

Reduces the execution time of the following code by ~4.5% on s390x:

for i := 0; i < N; i++ {
        x += (uint64(i)<<32)>>32
}

Change-Id: Idb2d56f27e80a2e1366bc995922ad3fd958c51a7
Reviewed-on: https://go-review.googlesource.com/37292Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

ExampleSliceStable echoes the sort.Slice example, to demonstrate sorting
on two fields together preserving order between sorts.

Change-Id: I8afc20c0203991bfd57260431eda73913c165355
Reviewed-on: https://go-review.googlesource.com/37196Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>