In faketime mode, checkdead is responsible for jumping time forward to
the next timer expiration, and waking an M to handle the newly ready
timer.
Currently it pulls the exact P that owns the next timer off of the pidle
list. In theory this is efficient because that P is immediately eligible
to run the timer without stealing. Unfortunately it is also fraught with
peril because we are skipping all of the bookkeeping in pidleget:
* Skipped updates to timerpMask mean that our timers may not be eligible
for stealing, as they should be.
* Skipped updates to idlepMask mean that our runq may not be eligible
for stealing, as they should be.
* Skipped updates to sched.npidle may break tracking of spinning Ms,
potentially resulting in lost work.
* Finally, as of CL 410122, skipped updates to p.limiterEvent may affect
the GC limiter, or cause a fatal throw when another event occurs.
The last case has finally undercovered this issue since it quickly
results in a hard crash.
We could add all of these updates into checkdead, but it is much more
maintainable to keep this logic in one place and use pidleget here like
everywhere else in the runtime. This means we probably won't wake the
P owning the timer, meaning that the P will need to steal the timer,
which is less efficient, but faketime is not a performance-sensitive
build mode. Note that the M will automatically make itself a spinning M
to make it eligible to steal since it is the only one running.
Fixes#53294
For #52890
Change-Id: I4acc3d259b9b4d7dc02608581c8b4fd259f272e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/411119
Run-TryBot: Michael Pratt <mpratt@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
We use str.TrimFilePathPrefix to trim the module root prefix and get the
relative path of each package in the module when scanning the module
and in the RelPath function. Make sure to clean the path before
indexing and in RelPath to ensure that each path starts with that
prefix, because walk will clean the root path before joining each
subdirectory path to it.
Change-Id: I1dc1eddbd42030eb6d5d8e76a8675f94216447c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/411118
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
Setgroups in syscall_linux.go already wraps the setgroups(2) syscall
with correct POSIX semantics (ref. CL 210639).
Change-Id: I961cd7c7fce1d70d23bf13cc82cad17854bbf40e
Reviewed-on: https://go-review.googlesource.com/c/go/+/411214
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Very rarely, GDB will successfully run the whole test and the inferior
will exit successfully, and then GDB itself hangs and never exits.
Detect this and skip the test as flaky. We could just continue the
test since all of the output we need is there, but by skipping it
we're less likely to notice serious regressions in this test.
Fixes#37405.
Change-Id: I016cbb06f48673f064733da3e3f1ddcbefd58159
Reviewed-on: https://go-review.googlesource.com/c/go/+/411117
Reviewed-by: Cherry Mui <cherryyz@google.com>
CL 410754 introduces a race accessing the global testHookDialTCP hook.
Avoiding this race is difficult, since Dial can return while
goroutines it starts are still running. Add a version of this
hook to sysDialer, so it can be set on a per-test basis.
(Perhaps other uses of this hook should be moved to use the
sysDialer-local hook, but this change fixes the immediate data race.)
For #52173.
Change-Id: I8fb9be13957e91f92919cae7be213c38ad2af75a
Reviewed-on: https://go-review.googlesource.com/c/go/+/410957
Run-TryBot: Damien Neil <dneil@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
This changes the module index to be enabled by default, rather than
disabled by default. The index can still be disabled by setting
GODEBUG=index=0.
Fixes#53290.
Change-Id: Ic3728fc69d96bb6ef56b56e8c9f2dce35f2923cc
Reviewed-on: https://go-review.googlesource.com/c/go/+/410821
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
PackageModuleRoot needs to be called with the package's path, not
its directory on disk.
Change-Id: I080fe8ce2aeb72e1466624db81595a00915606bb
Reviewed-on: https://go-review.googlesource.com/c/go/+/410820
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
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Run-TryBot: Michael Matloob <matloob@golang.org>
This change replicates the behavior filed in issue #37015 for packages
imported from the module index. That behavior is that packages that
happen to exist in a GOPATH src directory have p.Root and p.Target set
even when the packages are loaded from modules. This is likely
unintentional behavior because in module mode, packages shouldn't behave
differently depending on whether their directories exist in GOPATH. But
for uniformity, (and because two of our tests depend on this behavior),
this CL will implement this behavior. We can remove it from the module
index when we remove it from the go/build logic.
Change-Id: I3f501c92fbb76eaf86b6b9275539f2129b67f884
Reviewed-on: https://go-review.googlesource.com/c/go/+/410822
Reviewed-by: Michael Matloob <matloob@golang.org>
Run-TryBot: Michael Matloob <matloob@golang.org>
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Reviewed-by: Russ Cox <rsc@golang.org>
The crypto ones were done in a separate CL and didn't merge well.
Same for runtime/debug.
The others are stale.
For #51400.
Change-Id: Iadb4de94d21cd6a20f52277a1c3d7800a729b81e
Reviewed-on: https://go-review.googlesource.com/c/go/+/411115
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Russ Cox <rsc@golang.org>
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Reviewed-by: David Chase <drchase@google.com>
libfuzzerHookStrCmp is manually reformatted into a proper go doc list.
We don't always format testdata, but these test programs are standard Go
programs that can be formatted.
Change-Id: I4dde398bca225ae8c72e787e4d43fd0ccfd0a90b
Reviewed-on: https://go-review.googlesource.com/c/go/+/411114
Auto-Submit: Michael Pratt <mpratt@google.com>
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Reviewed-by: Cherry Mui <cherryyz@google.com>
The ones I left behind are almost entirely ones that I see pending CLs for.
Also make various fixes to existing text.
For #51400.
Change-Id: I555e0074c9df82b5bdb345e21a08c8757ca147b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/410814
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
CL 389354 removed the fallback to pipe on all platforms with pipe2. This
is the case for linux. Thus, pipe and setNonblock are no longer needed
on linux/loong64 too.
Change-Id: I089adf918d0fd8de5d4d61a893707a2660f89183
Reviewed-on: https://go-review.googlesource.com/c/go/+/410736
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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Fixes#47214.
Change-Id: I6fdc1c4340c0943b825ac22e311179ad1cf30915
Reviewed-on: https://go-review.googlesource.com/c/go/+/410334
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
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Reviewed-by: Cherry Mui <cherryyz@google.com>
accept is no longer used on Linux since CL 346849 changed Accept to use
accept4 only.
This follows CL 386415 which already removed accept on all other Linux
platforms before the linux/loong64 port was submitted.
For #45964
Change-Id: I26945ff780e71174a0b0c2f5313c4bc1e1cbf786
Reviewed-on: https://go-review.googlesource.com/c/go/+/410737
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
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TestDialParallel is testing the Happy Eyeballs algorithm implementation,
which dials IPv4 and IPv6 addresses in parallel with the preferred
address family getting a head start. This test doesn't care about
the actual network operations, just the handling of the parallel
connections.
Use testHookDialTCP to replace socket creation with a function that
returns successfully, with an error, or after context cancellation
as required.
Limit tests of elapsed times to a check that the fallback deadline
has been exceeded in cases where this is expected.
This should fix persistent test flakiness.
Fixes#52173.
Change-Id: Ic93f270fccb63b24a91105a4d541479fc33a2de4
Reviewed-on: https://go-review.googlesource.com/c/go/+/410754
Auto-Submit: Damien Neil <dneil@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Damien Neil <dneil@google.com>
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With this change, the termlist String() function prints termlists
in the usual Go notation and thus we can use it in error reporting.
Preparation for fixing #40350.
For #40350.
Change-Id: Ia28318841305de234a71af3146ce0c59f5e601a5
Reviewed-on: https://go-review.googlesource.com/c/go/+/410894
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
This addresses comments from CL 410356.
For #48409.
For #51400.
Change-Id: I03560e820a06c0745700ac997b02d13bc03adfc6
Reviewed-on: https://go-review.googlesource.com/c/go/+/410735
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
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Reviewed-by: Russ Cox <rsc@golang.org>
For #51400
Change-Id: I964e52e0a36e7bbe77175670e93ce8c99e7dab6d
Reviewed-on: https://go-review.googlesource.com/c/go/+/410367
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Fill in the details of outstanding TODO items for go/types changes.
For #51400
Change-Id: Ib40d75fa1018aa164022cb49b293795dd597d49d
Reviewed-on: https://go-review.googlesource.com/c/go/+/410815
Run-TryBot: Robert Findley <rfindley@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
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Reviewed-by: Robert Griesemer <gri@google.com>
Use the program counter to compute the address of the first instruction
of the ret sled. The ret sled is located after 5 instructions from the
MOVD instruction saving the value of the program counter.
Change-Id: Ie7ae7a0807785d6fea035cf7a770dba7f37de0ec
GitHub-Last-Rev: 2719208c6a
GitHub-Pull-Request: golang/go#53039
Reviewed-on: https://go-review.googlesource.com/c/go/+/407895
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Alan Donovan <adonovan@google.com>
Both GNU and LLVM linkers de facto accept `-zPARAM`, and Go sometimes
does it. Inconsistently: there are more uses of `-z PARAM` than
`-zPARAM`:
$ git grep -E -- '-Wl,-z[^,]' master | wc -l
4
$ git grep -E -- '-Wl,-z,' master | wc -l
7
However, not adding a space between `-z` and the param is not
documented:
llvm-13:
$ man ld.lld-13 | grep -E -A1 -w -- "^ +-z"
-z option
Linker option extensions.
gnu ld:
$ man ld | grep -E -A1 -w -- "^ +-z"
-z keyword
The recognized keywords are:
--
-z defs
Report unresolved symbol references from regular object files. This is done even if the linker is creating a non-symbolic
--
-z muldefs
Normally when a symbol is defined multiple times, the linker will report a fatal error. These options allow multiple definitions
--
-z
--imagic
... and thus should be avoided.
`zig cc`, when used as the C compiler (`CC="zig cc" go build ...`), will
bark, because `zig cc` accepts only `-z PARAM`, as documented.
Closesziglang/zig#11669
Change-Id: I758054ecaa3ce01a72600bf65d7f7b5c3ec46d09
GitHub-Last-Rev: e068e007da
GitHub-Pull-Request: golang/go#53030
Reviewed-on: https://go-review.googlesource.com/c/go/+/407834
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Boringcrypto has never been officially supported and it remains unsupported.
It need not be mentioned in the release notes.
Change-Id: I24a08d424982615244d51c1d250035d85a602023
Reviewed-on: https://go-review.googlesource.com/c/go/+/410362
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
CL 410244 changes relnote to look for api file changes as well
as references to proposal issues, finding various things that
were missing from the release notes.
This CL adds the TODOs that the updated relnote found.
For #51400.
Change-Id: I512a9b8f1349a6c68c8a6979f55a07964d630175
Reviewed-on: https://go-review.googlesource.com/c/go/+/410361
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
This change resolves some TODOs in the release notes, and while we're
here, also clarifies how CPU profile samples are represented in runtime
traces.
Change-Id: Idaa36ccf65b03fd5463b2d5da682d3fa578d2f46
Reviewed-on: https://go-review.googlesource.com/c/go/+/410356
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Austin Clements <austin@google.com>
A few of these are copied from the memory model doc.
Many are entirely new, following discussion on #47141.
See https://research.swtch.com/gomm for background.
The rule we are establishing is that each type that is meant
to help synchronize a Go program should document its
happens-before guarantees.
For #50859.
Change-Id: I947c40639b263abe67499fa74f68711a97873a39
Reviewed-on: https://go-review.googlesource.com/c/go/+/381316
Auto-Submit: Russ Cox <rsc@golang.org>
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
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Reviewed-by: Roland Shoemaker <roland@golang.org>
In a set of 55M Go doc comments drawn from the latest version of
all public Go modules known to the module proxy in spring 2020,
the current Go 1.19 gofmt reformats about 1.57M of them.
Out of those 1.57M comments, inspection of random samples
shows that around 5% of the changed comments contain
unindented code snippets, multiline shell commands, or lists.
For example:
// Here is a greeting:
//
// func main() {
// fmt.Println("hello, world")
// }
// Run this command:
//
// path/to/your/program -flag1=longargument1 \
// -flag2=longargument2 \
// -flag3
// There are three possibilities:
//
// - Unindented code snippets (or JSON objects)
// in which the first and last line are unindented
// but end in { and start with }, respectively.
// - Unindented multiline shell commands
// in which the lines end in \
// - Unindented lists, in which wrapped lines are indented.
All three of these cases involve unindented lines next to indented
lines that would according to the usual rules begin a pre block.
Before this CL, they'd be reformatted to:
// Here is a greeting:
//
// func main() {
//
// fmt.Println("hello, world")
//
// }
// Run this command:
//
// path/to/your/program -flag1=longargument1 \
//
// -flag2=longargument2 \
// -flag3
// There are three possibilities:
//
// - Unindented code snippets (or JSON objects)
//
// in which the first and last line are unindented
// but end in { and start with }, respectively.
//
// - Unindented multiline shell commands
//
// in which the lines end in \
//
// - Unindented lists, in which wrapped lines are indented.
The fact that they are not already in canonical format gives us
a signal that they might not mean what the usual rules would say.
This CL takes advantage of that opening to apply a few heuristics
to better handle these cases:
1. If an indented code block immediately follows (without a blank line)
an unindented line ending in { or \, include the unindented line
in the code block.
2. If an indented code block immediately precedes (without a blank line)
an unindented line beginning with }, include the unindented line
in the code block.
3. If an indented line immediately follows (without a blank line)
an unindented line that starts with a list marker, assume this is
an unindented list with a wrapped indented line, and treat all
adjacent unindented lines starting with list markers as part of
the list, stopping at any surrounding blank lines.
This raises the fraction of “correctly” reformatted doc comments
in the corpus from approximately 87% to approximately 93%.
Change-Id: I7ac542eb085032d607a7caf3ba9020787b2978b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/410360
Auto-Submit: Russ Cox <rsc@golang.org>
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Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
CL 381315 added major revisions but neglected to update the date.
For #50859.
Change-Id: I086a55f0c80579c479bca5268109c9f3ae680adf
Reviewed-on: https://go-review.googlesource.com/c/go/+/410675
Reviewed-by: Roland Shoemaker <roland@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Russ Cox <rsc@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
If we're trying to search in a module in the module cache, instead
iterate over the packages in the index.
Change-Id: Ia94cbe6e9690110c28b93dbb33810680e3010381
Reviewed-on: https://go-review.googlesource.com/c/go/+/403756
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Peter Weinberger <pjw@google.com>
Run-TryBot: Michael Matloob <matloob@golang.org>
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This CL addresses the comments on CL 403154.
For #51940.
Change-Id: I99bb3530916d469077bfbd53095bfcd1d2aa82ef
Reviewed-on: https://go-review.googlesource.com/c/go/+/403976
Reviewed-by: Roland Shoemaker <roland@golang.org>
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``` is Markdown, not Go doc comment, but some small fraction of users get confused.
In a set of 55M Go doc comments drawn from the latest version of
all public Go modules known to the module proxy in spring 2020,
the current Go 1.19 gofmt reformats about 1.57M of them.
Out of those 1.57M comments, 8k of them (about 0.5%) contain ```.
Instead of rewriting ``` to “`, leave it alone.
For #51082.
Change-Id: I1c8c88aac7ef75ec03e1a396b84ffe711c46f941
Reviewed-on: https://go-review.googlesource.com/c/go/+/410359
Reviewed-by: Ian Lance Taylor <iant@google.com>
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A CL in the website repo will add go.dev/doc/comment.
One of the final steps for #51082.
Change-Id: I419b4f6dbb424a8a93a8d09db30f7321af9ae976
Reviewed-on: https://go-review.googlesource.com/c/go/+/410358
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This appeases Go 1.4, making it possible to bootstrap GOARCH=riscv64 with
a Go 1.4 compiler.
Fixes#52583
Change-Id: Ib13c2afeb095b2bb1464dcd7f1502574209bc7ab
Reviewed-on: https://go-review.googlesource.com/c/go/+/409974
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Reviewed-by: Cherry Mui <cherryyz@google.com>
strings for 'NaN' -> string for 'NaN'
Change-Id: Ia415644a1b651e6ef9996ad24dd9708a60e57dfc
GitHub-Last-Rev: 877f1c3eb1
GitHub-Pull-Request: golang/go#53246
Reviewed-on: https://go-review.googlesource.com/c/go/+/410494
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Reviewed-by: Cherry Mui <cherryyz@google.com>
When building CGO internal linking on windows 386, make sure to avoid
rewriting references to "_main" to "main" when reading symbols during
host object loading; the main routine defined by the Go runtime is
still named "_main" (not "main"). If we don't do this, we wind up with
an SXREF symbol named "main", which can then cause the loader to pull
an actual "main" symbol out of a host archive, which is undesirable.
Updates #35006.
Change-Id: I3768e3617b560552f4522e9e72af879c6adf7705
Reviewed-on: https://go-review.googlesource.com/c/go/+/410124
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Auto-Submit: Than McIntosh <thanm@google.com>
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Now that validType is using the correct type nest (CL 409694),
the top entry of the type nest corresponds to the instantiated
type. Thus we can use that type instance to look up the value
of type parameters, there's no need anymore to create an environment
to look up type arguments.
Remove the need to pass around the environment and remove all
associated types and functions.
Updates #52698.
Change-Id: Ie37eace88896386e667ef93c77a4fc3cd0be6eb9
Reviewed-on: https://go-review.googlesource.com/c/go/+/410294
Reviewed-by: Robert Findley <rfindley@google.com>
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Run-TryBot: Robert Griesemer <gri@google.com>
validType was using a global type info map to detect invalid recursive
types, which was incorrect. Instead, change the algorithm as follows:
- Rather than using a "seen" (or typeInfo) map which is cumbersome to
update correctly, use the stack of embedding types (the type nest)
to check whether a type is embedded within itself, directly or
indirectly.
- Use Identical for type comparisons which correctly considers identity
of instantiated generic types.
- As before, maintain the full path of types leading to a cycle. But
unlike before, track the named types rather than their objects, for
a smaller slice ([]*Named rather than []Object), and convert to an
object list only when needed for error reporting.
- As an optimization, keep track of valid *Named types (Checker.valids).
This prevents pathological cases from consuming excessive computation
time.
- Add clarifying comments and document invariants.
Based on earlier insights by David Chase (see also CL 408818).
Fixes#52698.
Change-Id: I5e4598c58afcf4ab987a426c5c4b7b28bdfcf5ea
Reviewed-on: https://go-review.googlesource.com/c/go/+/409694
Reviewed-by: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
