Revert CL 101715.
The size of a sync.Pool scales linearly with GOMAXPROCS,
making it inappropriate to put a sync.Pool in any individually
allocated object, as the sync.Pool documentation explains.
The change also broke DeepEqual on regexps.
I have a cleaner way to do this with global sync.Pools but it's
too late in the cycle. Will revisit in Go 1.12. For now, revert.
Fixes#26219.
Change-Id: Ie632e709eb3caf489d85efceac0e4b130ec2019f
Reviewed-on: https://go-review.googlesource.com/122596
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Original CL description:
When using test -cover or -coverprofile the output for "no test files"
is the same format as for "no tests to run".
Reverting because this CL changed cmd/go to build test binaries for
packages that have no tests, leading to extra work and confusion.
Updates #24570Fixes#25789Fixes#26157Fixes#26242
Change-Id: Ibab1307d39dfaec0de9359d6d96706e3910c8efd
Reviewed-on: https://go-review.googlesource.com/122518
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
This test is skipped on Linux and should be skipped on Android for the
same reason.
Change-Id: I753c4788d935bd58874554b455c0d5be2315b794
Reviewed-on: https://go-review.googlesource.com/122585
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
CL 122515 tightened TestAbort to look for breakpoint exceptions and
not just general signal crashes, but this only applies on x86 arches.
On non-x86 arches we use a nil pointer dereference to abort, so the
test is now failing.
This CL re-loosens TestAbort on non-x86 arches to only expect a signal
traceback.
Should fix the build on linux/arm, linux/arm64, linux/ppc64, and
linux/s390x.
Change-Id: I1065341180ab5ab4da63b406c641dcde93c9490b
Reviewed-on: https://go-review.googlesource.com/122580
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Since CL 122515, TestAbort is failing on Plan 9
because there is no SIGTRAP signal on Plan 9,
but a note containing the "sys: breakpoint" string.
This change fixes the TestAbort test by handling
the Plan 9 case.
Fixes#26265.
Change-Id: I2fae00130bcee1cf946d8cc9d147a77f951be390
Reviewed-on: https://go-review.googlesource.com/122464
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Currently, if the runtime overflows the g0 stack on Windows, it leads
to an infinite recursion:
1. Something overflows the g0 stack bounds and calls morestack.
2. morestack determines it's on the g0 stack and hence cannot grow the
stack, so it calls badmorestackg0 (which prints "fatal: morestack on
g0") followed by abort.
3. abort performs an INT $3, which turns into a Windows
_EXCEPTION_BREAKPOINT exception.
4. This enters the Windows sigtramp, which ensures we're on the g0
stack and calls exceptionhandler.
5. exceptionhandler has a stack check prologue, so it determines that
it's out of stack and calls morestack.
6. goto 2
Fix this by making the exception handler avoid stack checks until it
has ruled out an abort and by blowing away the stack bounds in
lastcontinuehandler before we print the final fatal traceback (which
itself involves a lot of stack bounds checks).
Fixes#21382.
Change-Id: Ie66e91f708e18d131d97f22b43f9ac26f3aece5a
Reviewed-on: https://go-review.googlesource.com/120857
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Windows includes an 8K guard in system-allocated thread stacks, which
we currently don't account for when setting the g0 stack bounds. As a
result, if we do overflow the g0 stack bounds, we'll get a
STATUS_GUARD_PAGE_VIOLATION exception, which we're not expecting.
Fix the g0 stack bounds to include a total of 16K of slop to account
for this 8K guard.
Updates #21382.
Change-Id: Ia89b741b1413328e4681a237f5a7ee645531fe16
Reviewed-on: https://go-review.googlesource.com/122516
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
On Windows, the IP recorded in the breakpoint exception caused by
runtime.abort is actually one byte after the INT3, unlike on UNIX
OSes. Account for this in isgoexception.
It turns out TestAbort was "passing" on Windows anyway because abort
still caused a fatal panic, just not the one we were expecting. This
CL tightens this test to check that the runtime specifically reports a
breakpoint exception.
Fixing this is related to #21382, since we use runtime.abort in
reporting g0 stack overflows, and it's important that we detect this
and not try to handle it.
Change-Id: I66120944d138eb80f839346b157a3759c1019e34
Reviewed-on: https://go-review.googlesource.com/122515
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
The ADDLmodify/SUBLmodify/ANDLmodify/ORLmodify/XORLmodify should
have clobberFlags set to true.
Change-Id: Ie447d536db51334eddc70c00a722647282186a69
Reviewed-on: https://go-review.googlesource.com/122556
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reportedly CIFS on RHEL 7 can fail to report files if directories are
read in 4K increments. While this seems to be a CIFS or RHEL bug,
reportedly CIFS does not return more than 5760 bytes in a block, so
reading in 8K increments should hide the problem from users with
minimal cost.
Fixes#24015
Change-Id: Iaf9f00ffe338d379c819ed9edcd4cc9834e3b0f7
Reviewed-on: https://go-review.googlesource.com/121756
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Expanding interface method sets is handled during width calculation,
which can't be performed concurrently. Make sure that we eagerly
expand interfaces in the frontend when importing them, even if they're
not actually used by code, because we might need to generate a type
description of them.
Fixes#25055.
Change-Id: I6fd2756de2c7d5dbc33056f70b3028ca3aebab41
Reviewed-on: https://go-review.googlesource.com/122517
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Go documentation can have header lines, which are single-line paragraphs
with leading and trailing letters and almost no punctuation.
Before this CL, the only allowed punctuation was ' followed by s.
After this CL, parentheses and commas are also allowed,
to pick up a pair of previously unrecognized headings in the
go command documentation:
Gofmt (reformat) package sources
Modules, module versions, and more
Change-Id: I6d59c40a1269f01cef62a3fb17b909571c2f2adb
Reviewed-on: https://go-review.googlesource.com/122407
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Andrew Bonventre <andybons@golang.org>
CL 118095 added gitrepo tests. These tests are failing on Plan 9
since they expect a full-featured git command, while the git tool
has been emulated as a simple rc script on Plan 9.
Fixes#25938.
Change-Id: I262a89d0ce83168c550d9af3e832ed3a1e3c43f6
Reviewed-on: https://go-review.googlesource.com/122455
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This test is slightly flaky on the s390x builder and I suspect that
the 100ms timeout is a little too optimistic when the VM is starved.
Increase the timeout to 5s to match the other part of the test.
Fixes#26231.
Change-Id: Ia6572035fb3efb98749f2c37527d250a4c779477
Reviewed-on: https://go-review.googlesource.com/122315
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
I don't have access to this e-mail inbox anymore.
Change-Id: Ia3dff6a56c7f6c782be74a998a622ef0611eca7e
Reviewed-on: https://go-review.googlesource.com/122456
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
This function tests that calling Shutdown on a Server that has a "new"
connection yet to write any bytes, in which case it should wait for five
seconds until considering the connection as "idle".
However, the test was flaky. If Shutdown happened to run before the
server accepted the connection, the connection would immediately be
rejected as the server is already closed, as opposed to being accepted
in the "new" state. Then, Shutdown would return almost immediately, as
it had no connections to wait for:
--- FAIL: TestServerShutdownStateNew (2.00s)
serve_test.go:5603: shutdown too soon after 49.41µs
serve_test.go:5617: timeout waiting for Read to unblock
Fix this by making sure that the connection has been accepted before
calling Shutdown. Verified that the flake is gone after 50k concurrent
runs of the test with no failures, whereas the test used to fail around
10% of the time on my laptop:
go test -c && stress -p 256 ./http.test -test.run TestServerShutdownStateNew
Fixes#26233.
Change-Id: I819d7eedb67c48839313427675facb39d9c17257
Reviewed-on: https://go-review.googlesource.com/122355
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The maximum number of 'spanz' iterations that the s390x assembler
performs to reach a fixed point for relative offsets was 10. This
turned out to be too aggressive for one example of auto-generated
fuzzing code. Increase the number of iterations by 10x to reduce
the likelihood that the limit will be hit again. This limit only
exists to help find bugs in the assembler.
master at tip does not fail with the example code in the issue, I
have therefore not submitted it as a test (it is also quite large).
I tested this change with the example code at the commit given and
it fixes the issue.
Fixes#25269.
Change-Id: I0e44948957a7faff51c7d27c0b7746ed6e2d47bb
Reviewed-on: https://go-review.googlesource.com/122235
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Otherwise it is possible that msan will consider the C result to be
partially initialized, which may cause msan to think that the Go stack
is partially uninitialized. The compiler will never mark the stack as
initialized, so without this CL it is possible for stack addresses to
be passed to msanread, which will cause a false positive error from msan.
Fixes#26209
Change-Id: I43a502beefd626eb810ffd8753e269a55dff8248
Reviewed-on: https://go-review.googlesource.com/122196
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
There is no "window" global in a web worker context. Use "self" instead.
Fixes#26192
Change-Id: I6c6f3db6c3d3d9ca00a473f8c18b849bc07a0017
Reviewed-on: https://go-review.googlesource.com/122055
Run-TryBot: Richard Musiol <neelance@gmail.com>
Reviewed-by: Richard Musiol <neelance@gmail.com>
Use an HTML comment with triple dashes for the copypright header, which
means that the paragraph will be ignored when rendering both HTML and
TeX.
While at it, quote "GC", and properly link to internal/ssa/README.md.
Change-Id: Ib18529d2fc777d836e74726ff1cfe685e08b063c
Reviewed-on: https://go-review.googlesource.com/109875
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The implementation is mostly copied from the commit that added
linux/amd64 support for this feature (https://golang.org/cl/17761).
Change-Id: I3f482167620a7a3daf50a48087f8849a30d713bd
Reviewed-on: https://go-review.googlesource.com/102438
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
We already remove -rdynamic if -static appears in -extldflags.
Extend that to apply to CGO_LDFLAGS and #cgo LDFLAGS as well.
Updates #26197
Change-Id: Ibb62d1b20726916a12fd889acb05c1c559a5ace2
Reviewed-on: https://go-review.googlesource.com/122135
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Currently we use a globally unique symbol property on objects that get
passed from JavaScript to Go to store a unique ID that Go then uses when
referring back to the JavaScript object (via js.Value.ref). This
approach fails however when a JavaScript object cannot be modified, i.e.
cannot have new properties added or is frozen. The test that is added as
part of this commit currently fails with:
Cannot add property Symbol(), object is not extensible
Instead we consolidate the string, symbol and object unique ID mapping
into a single map. Map key equality is determined via strict equality,
which is the semantic we want in this situation.
Change-Id: Ieb2b50fc36d3c30e148aa7a41557f3c59cd33766
Reviewed-on: https://go-review.googlesource.com/121799
Run-TryBot: Paul Jolly <paul@myitcv.org.uk>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
Since the initial version was written, I've gotten help writing
cmd/compile/README.md and I've also learned some more on my own, so it's
time to organise this document better and expand it.
First, split up the document in sections, starting from the simplest
ideas that can be explained on their own. From there, build all the way
up into SSA functions and how they are compiled.
Each of the sections also gets more detail now; most ideas that were a
paragraph are now a section with several paragraphs. No new major
sections have been added in this CL.
While at it, add a copyright notice and make better use of markdown,
just like in the other README.md.
Also fix a file path in value.go, which I noticed to be stale while
reading godocs to write the document.
Finally, leave a few TODO comments for areas that would benefit from
extra input from people familiar with the SSA package. They will be
taken care of in future CLs.
Change-Id: I85e7a69a0b3260e72139991a625d926099624f71
Reviewed-on: https://go-review.googlesource.com/110067
Reviewed-by: Keith Randall <khr@golang.org>
When a command has a test that is not in package main, the main
package is built as a library, with ForceLibrary set. It can of course
also be built as an ordinary main package. If we don't record that fact
in the hash, then both variants of the command will use the same hash,
which causes a GODEBUG=gocacheverify=1 failure. It also seems unsafe
although it's not clear to me whether it can cause an actual failure.
Along with CL 121941,
Fixes#25666
Change-Id: I115ad249012f30fbe45cd0c41da86adc295fe4b2
Reviewed-on: https://go-review.googlesource.com/121942
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The linker's sym.Symbol struct contains two string fields, "Dynimplib"
and "Dynimpvers" that are used only in very specific circumstances
(for many symbols, such as DWARF syms, they are wasted space). Split
these two off into a separate struct, then point to an instance of
that struct when needed. This reduces the size of sym.Symbol so as to
save space in the common case.
Updates #26186
Change-Id: Id9c74824e78423a215c8cbc105b72665525a1eff
Reviewed-on: https://go-review.googlesource.com/121916
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The sym.Symbol 'Reachparent' field is used only when field tracking
is enabled. So as to use less memory for the common case where
field tracking is not enabled, remove this field and use a side
table stored in the context to achieve the same functionality.
Updates #26186
Change-Id: Idc5f8b0aa323689d4d51dddb5d1b0341a37bb7d2
Reviewed-on: https://go-review.googlesource.com/121915
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Before CL 116855, Transport would only skip over 100 (expect-continue)
responses automatically and treat all other 1xx responses as if they
were the final status. CL 116855 made the Transport more spec
compliant (ignoring unknown 1xx responses), but broke "101 Switching
Protocols" in the process. Since 101 is already in use and defined to
not have a following message, treat it as terminal.
Note that because the Client/Transport don't support hijacking the
underlying Conn, most clients doing a WebSocket or other protocol
upgrade are probably using net.Dial + http.ReadResponse instead, which
remained unaffected (before & after this CL).
The main affect of this CL is to fix tests that were using the
Client/Transport to test that a server returns 101, presumably without
actually switching to another protocol.
Fixes#26161
Change-Id: Ie3cd3a465f948c4d6f7ddf2a6a78a7fb935d0672
Reviewed-on: https://go-review.googlesource.com/121860
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The vetx output file is a build output, and as such should be
deterministic. This CL changes it to not depend on map iteration order.
This avoids a pointless GODEBUG=gocacheverify=1 failure.
Updates #25666
Change-Id: Ic132bad134cb10938275f883c2c68432cb7c4409
Reviewed-on: https://go-review.googlesource.com/121941
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Late opt pass may generate dead stores, which messes up store
chain calculation in later passes. Run generic deadcode even
in -N mode to remove them.
Fixes#26163.
Change-Id: I8276101717bb978d5980e6c7998f53fd8d0ae10f
Reviewed-on: https://go-review.googlesource.com/121856
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
These rules don't even type check. ADDQconstmodify returns memory,
and it is being rewritten to a value that returns an int64.
There should be a MOVQstore wrapped around the result.
These rules never fire during all.bash, so they aren't even tested.
I'm just going to remove them for now.
Change-Id: I76008eb51ae4e16c707fac73c05a8d67cac149ae
Reviewed-on: https://go-review.googlesource.com/121935
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
If the address of an auto reaches a phi then any further stores to
the pointer represented by the phi probably need to be kept. This
is because stores to the other arguments to the phi may be visible
to the program.
Fixes#26153.
Change-Id: Ic506c6c543bf70d792e5b1a64bdde1e5fdf1126a
Reviewed-on: https://go-review.googlesource.com/121796
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Fixes#26173
Change-Id: I032551f63b359c8cbb7296931e1957d2bff8f328
Reviewed-on: https://go-review.googlesource.com/121819
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
TestUtimesNanoAt in the vendored copy of golang.org/x/sys/unix currently
fails on the linux-arm-arm5spacemonkey builder. Update the vendored copy
to pick up the fix from CL 120816.
Updates #26034
Change-Id: I75c8875089f58a4c32e2e7aa75884b2bcba7bd68
Reviewed-on: https://go-review.googlesource.com/121800
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Currently, on Windows, the thread stack size is set or assumed in many
different places. In non-cgo binaries, both the Go linker and the
runtime have a copy of the stack size, the Go linker sets the size of
the main thread stack, and the runtime sets the size of other thread
stacks. In cgo binaries, the external linker sets the main thread
stack size, the runtime assumes the size of the main thread stack will
be the same as used by the Go linker, and the cgo entry code assumes
the same.
Furthermore, users can change the main thread stack size using
editbin, so the runtime doesn't even really know what size it is, and
user C code can create threads with unknown thread stack sizes, which
we also assume have the same default stack size.
This is all a mess.
Fix the corner cases of this and the duplication of knowledge between
the linker and the runtime by querying the OS for the stack bounds
during thread setup. Furthermore, we unify all of this into just
runtime.minit for both cgo and non-cgo binaries and for the main
thread, other runtime-created threads, and C-created threads.
Updates #20975.
Change-Id: I45dbee2b5ea2ae721a85a27680737ff046f9d464
Reviewed-on: https://go-review.googlesource.com/120336
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Currently, we allocate 1MB or 2MB thread stacks on Windows, but in
non-cgo binaries still set the g0 stack bounds assuming only 64k is
available. While this is fine in pure Go binaries, a non-cgo Go binary
on Windows can use the syscall package to call arbitrary DLLs, which
may call back into Go. If a DLL function uses more than 64k of stack
and then calls back into Go, the Go runtime will believe that it's out
of stack space and crash.
Fix this by plumbing the correct stack size into the g0 stacks of
non-cgo binaries. Cgo binaries already use the correct size because
their g0 stack sizes are set by a different code path.
Fixes#20975.
Change-Id: Id6fb559cfe1e1ea0dfac56d4654865c20dccf68d
Reviewed-on: https://go-review.googlesource.com/120195
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Executing tests in cmd/go/internal/modfetch/gitrepo/fetch_test.go in enviroment
witout outside connectivity in to the internet results in tests failure:
2018/06/25 12:48:26 git clone --mirror https://vcs-test.golang.org/git/gitrepo1 /tmp/gitrepo-test-221822392/gitrepo2 in : exit status 128:
Cloning into bare repository '/tmp/gitrepo-test-221822392/gitrepo2'...
fatal: unable to access 'https://vcs-test.golang.org/git/gitrepo1/': Could not resolve host: vcs-test.golang.org
FAIL cmd/go/internal/modfetch/gitrepo 0.144s
Call flag.Parse in TestMain to properly initialize test environment variables
Fixes#26007
Change-Id: I059e27db69c0ca0e01db724035a25d6fefb094b5
Reviewed-on: https://go-review.googlesource.com/120735
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The OpenBSD sysctl code has been copy-pasted three times now. Abstract
it.
Change-Id: Ia5558927f0bc2b218b5af425dab368b5485d266c
Reviewed-on: https://go-review.googlesource.com/121775
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
On the OpenBSD builder this reduces the test time from 213 seconds to
60 seconds, without loss of testing.
Not sure why the test is so much slower on OpenBSD, so not closing the
issues.
Updates #26155
Updates #26174
Change-Id: I13b58bbe3b209e591c308765077d2342943a3d2a
Reviewed-on: https://go-review.googlesource.com/121820
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ralph Corderoy <ralph@inputplus.co.uk>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
