Since the check tests are now identical between the two type checkers,
remove the local copy of the check tests and (for now) use the tests
in go/types/testdata/check instead. Eventually we may decide to move
all tests out of the type checker directories and place them in a
shared space (e.g. internal/types/testdata).
For #54511.
Change-Id: Id3a97593f6c705c5eda4566089ddc7aeb7b47337
Reviewed-on: https://go-review.googlesource.com/c/go/+/425736
Reviewed-by: Alan Donovan <adonovan@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Use the go/types version of testdata/check tests where the diffs
are only in the error positions (the types2 test harness allows
for some position tolerance). Consolidate files where there are
other minor differences.
Comment out a couple of tests that are different between the two
type checkers.
With this CL, the testdata/check files are identical between the
two type checkers.
For #54511.
Change-Id: Ibdff2ca3ec9bdaca3aa84029a7883bb83d2d2060
Reviewed-on: https://go-review.googlesource.com/c/go/+/425735
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Alan Donovan <adonovan@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
- Use "expected X" rather then "expecting X".
- Report a better error when a type argument list is expected.
- Adjust various tests.
For #54511.
Change-Id: I0c5ca66ecbbdcae1a8f67377682aae6b0b6ab89a
Reviewed-on: https://go-review.googlesource.com/c/go/+/425734
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
If the go/defer syntax is bad, using a fake CallExpr may produce
a follow-on error in the type checker. Instead store a BadExpr
in the syntax tree (since an error has already been reported).
Adjust various tests.
For #54511.
Change-Id: Ib2d25f8eab7d5745275188d83d11620cad6ef47c
Reviewed-on: https://go-review.googlesource.com/c/go/+/425675
Reviewed-by: Alan Donovan <adonovan@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Remove the code that verifies that an expression is a type or non-type
expression. For one, it cannot be done perfectly accurate
(e.g., consider *p which could be an indirection or a pointer type),
it also unnecessarily slows down parsing. It's simpler to leave the
verification to the type checker which has all the information needed.
Remove short compiler tests that tested the expression/type property.
Adjust a couple of go/types tests which now trigger because the parser
doesn't complain anymore.
Change file for benchmark from "parser.go" to "../printer/nodes.go"
to avoid a moving target when benchmarking.
The parser may be marginally faster when tested on nodes.go:
name old time/op new time/op delta
ParseOnly-12 1.35ms ± 0% 1.31ms ± 0% ~ (p=0.100 n=3+3)
name old speed new speed delta
ParseOnly-12 39.9MB/s ± 0% 41.0MB/s ± 0% ~ (p=0.100 n=3+3)
For #54511.
Change-Id: I9a32c24c2c6e843c3d1af4587651c352f378b490
Reviewed-on: https://go-review.googlesource.com/c/go/+/425716
Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Linux kernel 5.8 added the faccessat2 syscall taking a flags argument.
Attempt to use it in Faccessat and fall back to the existing
implementation mimicking glibc faccessat.
Do not export the new syscall value so we keep syscall API intact.
Part of this commit is generated by:
GOOS=linux ./mkall.sh -syscalls zsyscall_linux_*.go
This is similar to [1] amended by [2]. Required for [3].
[1] https://go-review.googlesource.com/c/sys/+/246537
[2] https://go-review.googlesource.com/c/sys/+/246817
[3] https://go-review.googlesource.com/c/go/+/414824
Co-authored-by: Tobias Klauser <tklauser@distanz.ch>
Change-Id: Ib7fe5ba853c15d92e869df9a16b56b79b96e43a6
Reviewed-on: https://go-review.googlesource.com/c/go/+/416115
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Amend the "mkall.sh -syscalls" implementation to
- prepend ./ before mksyscalls.pl;
- accept the optional file list argument.
This is a preparation for CL 416115.
Change-Id: Ib4dc2b4aa0d2dd22a256414864e92f2d2fd957a5
Reviewed-on: https://go-review.googlesource.com/c/go/+/423676
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Instead of passing the original length and the new length, pass
the new length and the length increment. Also use the new length
in all the post-growslice calculations so that the original length
is dead and does not need to be spilled/restored around the growslice.
old: growslice(typ, oldPtr, oldLen, oldCap, newLen) (newPtr, newLen, newCap)
new: growslice(oldPtr, newLen, oldCap, inc, typ) (newPtr, newLen, newCap)
where inc = # of elements added = newLen-oldLen
Also move the element type to the end of the call. This makes register
allocation more efficient, as oldPtr and newPtr can often be in the
same register (e.g. AX on amd64) and thus the phi takes no instructions.
Makes the go binary 0.3% smaller.
Change-Id: I7295a60227dbbeecec2bf039eeef2950a72df760
Reviewed-on: https://go-review.googlesource.com/c/go/+/418554
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Since when go1.17 is now used for bootstraping.
Change-Id: If28338fc82e6c61f057d7eb3a4c2ed77846167df
Reviewed-on: https://go-review.googlesource.com/c/go/+/427558
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: hopehook <hopehook@golangcn.org>
Since when go1.17 is now used for bootstraping.
Change-Id: I5f763dec1cb152f94ab1c677d3fa26da17abf097
Reviewed-on: https://go-review.googlesource.com/c/go/+/427557
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Keith Randall <khr@golang.org>
Run-TryBot: hopehook <hopehook@golangcn.org>
Reviewed-by: Keith Randall <khr@google.com>
Since when go1.17 is now used for bootstraping.
Change-Id: I5ee65aff72500a04e243238cffeae92ea659627b
Reviewed-on: https://go-review.googlesource.com/c/go/+/427555
Auto-Submit: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: hopehook <hopehook@golangcn.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@google.com>
These rules should belong to lowering rules not optimizations.
Change-Id: I964d2c4b1d9bef0ede572978aff01cb11bf050ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/426197
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Wayne Zuo <wdvxdr@golangcn.org>
We have supported passing lists of arguments to the compiler and linker
for some time, since https://go.dev/issue/18468 was fixed.
The reason behind it is that some systems like Windows have relatively
small limits for commands, and some Go packages contain many source files.
This wasn't done for other Go toolchain programs like cgo and asm,
as there wasn't an initial need for it. A TODO was left for them.
The need has now arisen in the form of a bug report for a build of a
large Go package involving cgo.
Do asm as well, which could be triggered by lots of asm files.
I rebuilt Go itself with some basic logging to tell if any other
commands were being run with moderately large command lengths.
I only found one other: gcc being invoked with 300-500 bytes.
I didn't spot any length close to 1KiB, and we can't safely assume that
a user's CC compiler supports these "response files", so leave that as
another TODO for the future. Just like cgo and asm, we can revisit this
if any user reports a bug on the issue tracker.
Fixes#47235.
Change-Id: Ifcc099d7c0dfac3ed2c4e9e7a2d6e3d69b0ccb63
Reviewed-on: https://go-review.googlesource.com/c/go/+/427015
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Since when go/types,types2 do not know about build constraints, and
runtime/cgo.Incomplete is only available on platforms that support cgo.
These tests are also failing on aix with failure from linker, so disable
them on aix to make builder green. The fix for aix is tracked in #54814
Updates #46731
Updates #54814
Change-Id: I5d6f6e29a8196efc6c457ea64525350fc6b20309
Reviewed-on: https://go-review.googlesource.com/c/go/+/427394
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
v.SetIterXXX(i) is semantically identical to v.Set(i.XXX()).
If the latter panics for unexported values, so should the former.
This change may breaking some programs, but the change is justified
under the "Go 1 and the Future of Go Programs" document because
the "library has a bug that violates the specification".
In this case, the "reflect" package does not accurately match
the behavior of the Go language specification.
Also, this API was recently released, so the number of users
who could be depending on this behavior is hopefully lower.
Fixes#54628
Change-Id: If86ede51f286e38093f6697944c089f616525115
Reviewed-on: https://go-review.googlesource.com/c/go/+/425184
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: David Chase <drchase@google.com>
Same as CL 421880, but for test directory.
Updates #46731
Change-Id: If8d18df013a6833adcbd40acc1a721bbc23ca6b2
Reviewed-on: https://go-review.googlesource.com/c/go/+/421881
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
After running the types2 type checker, walk info.Instances to reject
any not-in-heap type arguments. This is feasible to check using the
types2 API now, thanks to #46731.
Fixes#54765.
Change-Id: Idd2acc124d102d5a76f128f13c21a6e593b6790b
Reviewed-on: https://go-review.googlesource.com/c/go/+/427235
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@google.com>
In go.dev/cl/419674 I added a mechanism to the inliner to allow
inlining to fail gracefully when a function body is missing, but I
missed we already have a mechanism for that: typecheck.HaveInlineBody.
This CL makes it overridable so that unified IR can plug in its
appropriate logic, like it does with the logic for building the
ir.InlinedCallExpr node.
While here, rename inline.NewInline to inline.InlineCall, because the
name "NewInline" is now a misnomer since we initialize it to oldInline
(now named oldInlineCall).
Change-Id: I4e65618d3725919f69e6f43cf409699d20fb797c
Reviewed-on: https://go-review.googlesource.com/c/go/+/427234
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Rotating by c, then by d, is the same as rotating by c+d.
Change-Id: I36df82261460ff80f7c6d39bcdf0e840cef1c91a
Reviewed-on: https://go-review.googlesource.com/c/go/+/424894
Reviewed-by: Wayne Zuo <wdvxdr@golangcn.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Ruinan Sun <Ruinan.Sun@arm.com>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
The current mknode has a few problems:
1) It tends not to run successfully if the tree is in a broken state.
2) It requires that it be run by the go tool in the tree (somewhat related to 1)
3) It requires setting GOROOT
4) It imports code outside the tree (x/packages)
This makes mknode.go very fragile. In particular, I've spent lots of
time fighting mknode when adding or removing code, related to 1.
Rewrite to just use go/ast and friends. No typechecking, no importing,
etc. It can run with any go version, it doesn't need to be the one
corresponding to the code in which it is run. (e.g. you can use go
1.16 to run mknode). It will work as long as the ir package is parseable.
When run, it generates identical output to the old mknode.
Fixes#53959
Change-Id: I5ce0b55572ebcd2fcd11af57a5f29bbf9fa4ed33
Reviewed-on: https://go-review.googlesource.com/c/go/+/418375
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Currently we use a full cmpstring to do the comparison for each
split in the binary search for a string switch.
Instead, split by comparing a single byte of the input string with a
constant. That will give us a much faster split (although it might be
not quite as good a split).
Fixes#53333
R=go1.20
Change-Id: I28c7209342314f367071e4aa1f2beb6ec9ff7123
Reviewed-on: https://go-review.googlesource.com/c/go/+/414894
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
for i := 0; i < 9; i += 3
Currently we compute bounds of [0,8]. Really we know that it is [0,6].
CL 415874 computed the better bound as part of overflow detection.
This CL just incorporates that better info to the prove pass.
R=go1.20
Change-Id: Ife82cc415321f6652c2b5d132a40ec23e3385766
Reviewed-on: https://go-review.googlesource.com/c/go/+/415937
Reviewed-by: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
Since when internal linking cgo on some platforms, like android, is not
fully supported.
Updates #46731
Change-Id: I344a763f8dfb0cce04371d9305eee634bfd9ee77
Reviewed-on: https://go-review.googlesource.com/c/go/+/426199
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
The prove pass will mark some shifts bounded, and then we can use that
information to generate better code on riscv64.
Change-Id: Ia22f43d0598453c9417adac7017db28d7240948b
Reviewed-on: https://go-review.googlesource.com/c/go/+/422616
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Joel Sing <joel@sing.id.au>
Run-TryBot: Wayne Zuo <wdvxdr@golangcn.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
The negation does not change the comparison to zero.
Also remove unnecessary x.Uses == 1 condition from equivalent BEQZ/BNEZ rules.
Change-Id: I62dd8e383e42bfe5c46d11bbf78d8e5ff862a1d5
Reviewed-on: https://go-review.googlesource.com/c/go/+/426262
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
The result of these operations are already extended.
Change-Id: Ifc8ba362dda7035d8fd0d40046a96f61d3082877
Reviewed-on: https://go-review.googlesource.com/c/go/+/426260
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Meng Zhuo <mzh@golangcn.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Removes more than 2000 instructions from the Go binary on linux/risv64.
Change-Id: I6db3e3b1c93f29f00869adcba7c6192bfb90b25c
Reviewed-on: https://go-review.googlesource.com/c/go/+/426259
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Wayne Zuo <wdvxdr@golangcn.org>
Reviewed-by: Meng Zhuo <mzh@golangcn.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
A condition check was added to parse.go in CL 405542 to prevent
usage of scaled operands on ppc64. However while trying to improve
the error notification message, an if-condition was left out by
oversight. This CL corrects that.
Change-Id: I8cef3dd194c75343354ffe888b5e639e694badde
Reviewed-on: https://go-review.googlesource.com/c/go/+/426994
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Archana Ravindar <aravind5@in.ibm.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Previously the first operand of MSR could be $0, which would be
converted to the ZR register. This is prohibited by CL 404316,
this CL restores this instruction format.
Change-Id: I5b5be59e76aa58423a0fb96942d1b2a9de62e311
Reviewed-on: https://go-review.googlesource.com/c/go/+/426198
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Eric Fang <eric.fang@arm.com>
For #53821
Change-Id: I686fe81268f70acc6a4c3e6b1d3ed0e07bb0d61c
Reviewed-on: https://go-review.googlesource.com/c/go/+/425775
Run-TryBot: xie cui <523516579@qq.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Pratt <mpratt@google.com>
Note that this changes the non-atomic operations in p.destroy() to atomic operations.
For #53821
Change-Id: I7bba77c9a2287ba697c87cce2c79293e4d1b3334
Reviewed-on: https://go-review.googlesource.com/c/go/+/425774
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Note that this changes a non-atomic operation to atomic operation in gcStart().
For #53821
Change-Id: I754d254f6f190855144ff62151b6bae673b47867
Reviewed-on: https://go-review.googlesource.com/c/go/+/425776
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
And add some documentation for the debug query param.
Fixes#27737Fixes#53971
Change-Id: I629aaa2d4a43175381eb04872f1caad238519a41
Reviewed-on: https://go-review.googlesource.com/c/go/+/421635
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
If x+delta cannot overflow/underflow, we can derive:
x+delta < x if delta<0 (this CL included)
x+delta > x if delta>0 (this CL not included due to
a recursive stack overflow)
Remove 95 bounds checks during ./make.bat
Fixes#51622
Change-Id: I60d9bd84c5d7e81bbf808508afd09be596644f09
Reviewed-on: https://go-review.googlesource.com/c/go/+/406175
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Wayne Zuo <wdvxdr@golangcn.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Do not intercept integer compares that are used to increment libFuzzer's
8-bit counters. This is unnecessary and has a negative impact on the
fuzzing performance. This fixes#53760.
Change-Id: Id22efac968b18014eedabb6f0762e1456897024e
GitHub-Last-Rev: 52f69fd68c
GitHub-Pull-Request: golang/go#53786
Reviewed-on: https://go-review.googlesource.com/c/go/+/416796
Run-TryBot: Keith Randall <khr@golang.org>
Auto-Submit: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>