We currently use two fields to store the targets of branches.
Some phases use p.To.Val, some use p.Pcond. Rewrite so that
every branch instruction uses p.To.Val.
p.From.Val is also used in rare instances.
Introduce a Pool link for use by arm/arm64, instead of
repurposing Pcond.
This is a cleanup CL in preparation for some stack frame CLs.
Change-Id: If8239177e4b1ea2bccd0608eb39553d23210d405
Reviewed-on: https://go-review.googlesource.com/c/go/+/251437
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Also don't restart DWARF reading from beginning when we are testing
multiple entries.
Also reformat relocationTests slice to use indexed literals.
Change-Id: Ia5f17214483394d0ef033be516df61f0bdc521b6
Reviewed-on: https://go-review.googlesource.com/c/go/+/251637
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
When zero or less, maxIdleTime and maxLifetime means unlimited.
Helper function shortestIdleTimeLocked must not return the
minimum of the two until both are verified to be greater
then zero.
Fixes#40841
Change-Id: I1130332baf4ad259cd90c10f4221f5def8510655
Reviewed-on: https://go-review.googlesource.com/c/go/+/248817
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
The order array was zero initialized by the compiler, but ends up being
overwritten by the runtime anyway.
So let the runtime takes full responsibility for initializing, save us
one instruction per select.
Fixes#40399
Change-Id: Iec1eca27ad7180d4fcb3cc9ef97348206b7fe6b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/251517
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
The current command will run this entire set of tests, which takes a
noticeable amount of time. Contributors may wish to run only a subset of
these tests to save time/compute (e.g. when iterating on a CL that
failed tests in that subset). Listing file(s) as operands to the command
will run only those tests.
Change-Id: I1874c43681a594190bc40b61cee0b8d321be73f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/242997
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
This was fixed by CL 242084. Retroactively add some tests that would
have failed before the fix.
Also, remove some existing duplicate tests.
Change-Id: I95f7a215d4a9651ded6d739f89c574f33f573c60
Reviewed-on: https://go-review.googlesource.com/c/go/+/251397
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
There was some duplication of logic interpreting the implicit type of
an operand in assignableTo and convertUntyped. Factor out this logic to
a new 'implicitType' function, which returns the implicit type of an
untyped operand when used in a context where a target type is expected.
I believe this resolves some comments about code duplication. There is
other similar code in assignable, assignableTo, and convertUntypes, but
I found it to to be sufficiently semantically distinct to not warrant
factoring out.
Change-Id: I199298a2e58fcf05344318fca0226b460c57867d
Reviewed-on: https://go-review.googlesource.com/c/go/+/242084
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Flag constant Ops on arm and arm64 are under refactoring, this change adds
a couple of testcases that verify the behavior of 'noov' branches.
Updates #39505
Updates #38740
Updates #39303
Change-Id: I493344b52276900cd296c32da494d72932dfc9be
Reviewed-on: https://go-review.googlesource.com/c/go/+/238677
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Fixing several error message and comment texts of the ARM64 assembler
to use arrangement specifiers of Go's assembly style.
Change-Id: Icdbb14fba7aaede40d57d0d754795b050366a1ab
Reviewed-on: https://go-review.googlesource.com/c/go/+/237859
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
cmd/go.TestScript/test_main_twice demonstrates a program that invokes
(*M).Run twice in a row. If we only restore os.Exit(0) in m.afterOnce,
we will fail to restore it after the second run and fail the test
process despite both runs passing.
Updates #29062
Updates #23129
Change-Id: Id22ec68f1708e4583c8dda14a8ba0efae7178b85
Reviewed-on: https://go-review.googlesource.com/c/go/+/251262
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This reverts CL 243318.
Reason for revert: Seems to be crashing some builders.
Change-Id: I2ffc59bc5535be60b884b281c8d0eff4647dc756
Reviewed-on: https://go-review.googlesource.com/c/go/+/251169
Reviewed-by: Bryan C. Mills <bcmills@google.com>
We're using sort.SliceStable, so no need to keep track of indexes as well.
Use a more robust test for whether a node is a call.
Add a test that we're actually reordering comparisons. This test fails
without the alg.go changes in this CL because eqstring uses OCALLFUNC
instead of OCALL for its data comparisons.
Update #8606
Change-Id: Ieeec33434c72e3aa328deb11cc415cfda05632e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/237921
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This catches cases where a test calls code that calls os.Exit(0),
thereby skipping all subsequent tests.
Fixes#29062
Change-Id: If9478972f40189e27623557e7141469ca4234d89
Reviewed-on: https://go-review.googlesource.com/c/go/+/250977
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
This helps remove uses that aren't needed any more.
That in turn helps other rules with Uses==1 conditions fire.
Update #39918
Change-Id: I68635b675472f1d59e59604e4d34b949a0016533
Reviewed-on: https://go-review.googlesource.com/c/go/+/249463
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
We currently use two fields to store the targets of branches.
Some phases use p.To.Val, some use p.Pcond. Rewrite so that
every branch instruction uses p.To.Val.
p.From.Val is also used in rare instances.
Introduce a Pool link for use by arm/arm64, instead of
repurposing Pcond.
This is a cleanup CL in preparation for some stack frame CLs.
Change-Id: I9055bf0a1d986aff421e47951a1dedc301c846f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/243318
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
I think they are no longer experimental status. Might as well promote
them to permanent.
Change-Id: Id1259601b3dd2061dd60df86ee48080bfb575d2f
Reviewed-on: https://go-review.googlesource.com/c/go/+/249857
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
cgo parses GCC’s error messages to classify C identifiers referenced
from Go programs (are they integer constants? type names?). If GCC tries
to colorize its errors, cgo can’t figure out what GCC is saying. GCC
avoids escape sequences in this scenario by default, but the default
behavior can be overridden in at least two places:
- The user can set `CGO_COPTS=-fdiagnostics-color`.
- Whoever compiled GCC can configure GCC itself to always colorize
output.
The most reliable way to ensure that GCC doesn’t colorize output is to
append `-fdiagnostics-color=never` to the GCC command line; do so.
Fixes#40415
Change-Id: Id4bdf8d92fac8b038340b4264f726e8fe38875b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/248398
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This merges an lis + subf into subfic, and for 32b constants
lwa + subf into oris + ori + subf.
The carry bit is no longer used in code generation, therefore
I think we can clobber it as needed. Note, lowered borrow/carry
arithmetic is self-contained and thus is not affected.
A few extra rules are added to ensure early transformations to
SUBFCconst don't trip up earlier rules, fold constant operations,
or otherwise simplify lowering. Likewise, tests are added to
ensure all rules are hit. Generic constant folding catches
trivial cases, however some lowering rules insert arithmetic
which can introduce new opportunities (e.g BitLen or Slicemask).
I couldn't find a specific benchmark to demonstrate noteworthy
improvements, but this is generating subfic in many of the default
bent test binaries, so we are at least saving a little code space.
Change-Id: Iad7c6e5767eaa9dc24dc1c989bd1c8cfe1982012
Reviewed-on: https://go-review.googlesource.com/c/go/+/249461
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
runfinq may have write barriers, thus it may need to take wbufSpans on
any write.
Fixes#41021
Change-Id: Ib69e20994b5d7d1526ad53d6ddb5e2e83bf2ed00
Reviewed-on: https://go-review.googlesource.com/c/go/+/250464
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>
This is a port of CL 244628, updated to move some existing regression
tests into the fixedbugs directory, and to use subtests. Also,
'TestFixed' is renamed to 'TestFixedBugs'.
Change-Id: I43aac3f75f2bd850567d08e8b008d91aeb717064
Reviewed-on: https://go-review.googlesource.com/c/go/+/247904
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
This is a straightforward port of CL 244627.
Change-Id: Ide980957430b35e22a6e22818b0ce9de410988af
Reviewed-on: https://go-review.googlesource.com/c/go/+/247902
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Better still would be to avoid passing around module.Version instances
with invalid Version strings in the first place, so that any time we
see a module.Version we know that it is actually a version of a module
(and not a structurally-similar datum with something else tacked on to
one of the fields). But that's a bigger cleanup for which I don't
currently have enough bandwidth.
Fixes#41060
Change-Id: I32fba5619105cbf67dd03691064c82b8ebb3ce18
Reviewed-on: https://go-review.googlesource.com/c/go/+/250951
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
TestBenchmark is broken due to lack of a Config.Importer, but
unfortunately fails silently due to an unchecked error.
Fix the importer and check the error. Also improve the output to include
allocation stats.
Finally, don't run TestBenchmark on go/types by default. If the
benchmark is being used during a refactoring of go/types itself, results
for go/types will not be comparable.
Change-Id: Ib6bdb6807403b3ec99762f535e2496c94bd9b6e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/249517
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
Add s390x support to the addressing modes pass. This significantly
reduces the number of rules we need to have to handle indexed
addressing modes on s390x.
There are some changes introduced with the new approach. Notably
pointer calculations of the form '(ADD x (ADDconst y [c]))' won't
get fully merged into address fields right now, the constant offset
will remain separate. That is a relatively minor issue though.
file before after Δ %
addr2line 4120904 4120960 +56 +0.001%
api 4944005 4948765 +4760 +0.096%
asm 4977431 4984335 +6904 +0.139%
buildid 2683760 2683504 -256 -0.010%
cgo 4557976 4558408 +432 +0.009%
compile 19103577 18916634 -186943 -0.979%
cover 4883694 4885054 +1360 +0.028%
dist 3545177 3553689 +8512 +0.240%
doc 3921766 3921518 -248 -0.006%
fix 3295254 3302182 +6928 +0.210%
link 6539222 6540286 +1064 +0.016%
nm 4105085 4107757 +2672 +0.065%
objdump 4546015 4545439 -576 -0.013%
pack 2416661 2415485 -1176 -0.049%
pprof 13267433 13265489 -1944 -0.015%
test2json 2762180 2761996 -184 -0.007%
trace 10145090 10135626 -9464 -0.093%
vet 6772946 6771738 -1208 -0.018%
total 106588176 106418865 -169311 -0.159%
Fixes#37891.
Change-Id: If60d51f31eb2806b011432a6519951b8668cb42f
Reviewed-on: https://go-review.googlesource.com/c/go/+/250958
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
The AssignableTo API is specifically for non-constant values, but is
currently called by gopls for constant completions. Add a test to ensure
that we handle this edge case correctly.
Change-Id: I83115cbca2443a783df1c3090b5741260dffb78e
Reviewed-on: https://go-review.googlesource.com/c/go/+/250258
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
The error returned by convertUntyped is 'cannot convert _ to _', which
can be misleading in contexts where an explicit conversion would be
allowed.
Arguably the error message from convertUntyped should just be 'cannot
use _ as _', as 'convert' has an explicit meaning within the spec.
Making that change caused a large number of test failures, so for now we
just fix this for assignments by interpreting the error.
For #22070
Change-Id: I4eed6f39d1a991e8df7e035ec301d28a05150eb5
Reviewed-on: https://go-review.googlesource.com/c/go/+/242083
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
This restores the handling accidentally changed in CL 217377.
Fixes#40803
For #36959
Change-Id: If77fbc0c2a1dde4799f760affdfb8dde9bcaf458
Reviewed-on: https://go-review.googlesource.com/c/go/+/248598
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Jeremy Fishman <jfishman@cloudflare.com>
The intermediate SSA opcodes* are no longer generated during the
lowering pass. The shifting rules have been improved using ISEL.
Therefore, we can remove them and the rules which expand them.
* The removed opcodes are:
LoweredAdd64Carry
ADDconstForCarry
MaskIfNotCarry
FlagCarryClear
FlagCarrySet
Change-Id: I1ebe2726ed988f29ed4800c8f57b428f7a214cd0
Reviewed-on: https://go-review.googlesource.com/c/go/+/249462
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
This permits programs to reliably detect whether they are using a
closed network connection.
Fixes#4373
Change-Id: Ib4ce8cc82bbb134c4689f0ebc8b9b11bb8b32a22
Reviewed-on: https://go-review.googlesource.com/c/go/+/250357
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Russ Cox <rsc@golang.org>
This change rejects module paths that don't conform to
the new checkModulePathLax function, when loading a go.mod
file. The change uses the checkModulePathLax function instead of
CheckPath because there are still many users who are using
unpublished modules with unpublishable paths, and we don't
want to break them all.
Next, before this change, when go mod init is run in GOPATH,
it would try to use the location of the directory within GOPATH
to infer the module path. After this change, it will only use
that inferred module path if it conforms to module.CheckPath.
Change-Id: Idb36d1655cc76aae82671e87ba634609503ad1a2
Reviewed-on: https://go-review.googlesource.com/c/go/+/211597
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
For #24031
Change-Id: I9bd0905e9aacee4bec3463b7d91f6f0929744752
Reviewed-on: https://go-review.googlesource.com/c/go/+/228384
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
'go get' will now warn about retracted versions in the build list,
after updating go.mod. The warning instructs users to run
'go get module@latest' to upgrade or downgrade away from the retracted
version.
'go get' now allows users to explicitly request a specific retracted
version.
For #24031
Change-Id: I15fda918dc84258fb35b615dcd33b0f499481bd7
Reviewed-on: https://go-review.googlesource.com/c/go/+/228383
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
The -retracted flag causes 'go list' to load information about
retracted module module versions.
When -retracted is used with -f or -json, the Retracted field is set
to a string containing the reason for the retraction on retracted
module versions. The string is based on comments on the retract
directive. This field is also populated when the -u flag is used.
When -retracted is used with -versions, retracted versions are shown.
Normally, they are omitted.
For #24031
Change-Id: Ic13d516eddffb1b8404e21034f78cecc9896d1b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/228382
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
'go mod edit' can now add and remove 'retract' directives from go.mod
files.
Also, retractions are now included in the 'go mod edit -json' output.
For #24031
Change-Id: Ife7915e259fa508626d6ec5f786b5c860b489599
Reviewed-on: https://go-review.googlesource.com/c/go/+/228381
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
The go command now recognizes 'retract' directives in go.mod. A
retract directive may be used by a module author to indicate a
version should not be used. The go command will not automatically
upgrade to a retracted version. Retracted versions will not be
considered when resolving version queries like "latest" that don't
refer to a specific version.
Internally, when the go command resolves a version query, it will find
the highest release version (or pre-release if no release is
available), then it will load retractions from the go.mod file for
that version. Comments on retractions are treated as a rationale and
may appear in error messages. Retractions are only loaded when a query
is resolved, so this should have no impact on performance for most
builds, except when go.mod is incomplete.
For #24031
Change-Id: I17d643b9e03a3445676dbf1a5a351090c6ff6914
Reviewed-on: https://go-review.googlesource.com/c/go/+/228380
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Query and other functions now accept an "allowed" function that
returns an error (previously, the function returned a bool). If the
error is equivalent to ErrDisallowed, it indicates the version is
excluded (or, in a future CL, retracted). This provides predicates a
chance to explain why a version is not allowed.
When a query refers to a specific revision (by version, branch, tag,
or commit name), most callers will not use the Allowed predicate. This
allows commands like 'go list -m' and 'go mod download' to handle
disallowed versions when explicitly requested. 'go get' will reject
excluded versions though.
When a query does not refer to a specific revision (for example,
"latest"), disallowed versions will not be considered.
When an "allowed" predicate returns an error not equivalent to
ErrDisallowed, it may be ignored or returned, depending on the
case. This never happens for excluded versions, but it may happen for
retractions (in a future CL). This indicates a list of retractions
could not be loaded. This frequently happens when offline, and it
shouldn't cause a fatal or warning in most cases.
For #24031
Change-Id: I4df6fb6bd60e3e0259e5b3b4bf71a307b4b32298
Reviewed-on: https://go-review.googlesource.com/c/go/+/228379
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
This CL vendors go.mod parser changes for the retract directive.
For #24031
Change-Id: Ief19b0eca4c7956eceadc893bb209da7e9ecf22c
Reviewed-on: https://go-review.googlesource.com/c/go/+/228377
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>
Don't add a module declaration to a go.mod file when
loading a module. Require a user to call go mod init or to
add the module declaration themselves.
Fixes#35070
Change-Id: If5543580d3c1cfee1fc528eb853b872c4173ca82
Reviewed-on: https://go-review.googlesource.com/c/go/+/234107
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
While reading the source code of the math/big package, I found the SetString function example of float type missing.
Change-Id: Id8c16a58e2e24f9463e8ff38adbc98f8c418ab26
Reviewed-on: https://go-review.googlesource.com/c/go/+/232804
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
cmd/internal/objabi/doc.go has comments decribing the (old)
object file format. But cmd/internal/objabi has nothing to do
with object files, and never did. Delete.
Move some comment to cmd/internal/goobj, where the (new) object
file format is actually defined, and update to reflect the
current status.
Change-Id: Ied96089df4be35e5d259a572ed60ee00f2cd0d1d
Reviewed-on: https://go-review.googlesource.com/c/go/+/249958
Reviewed-by: Than McIntosh <thanm@google.com>
This CL applies strong aux typing to the remaining s390x rewrite
rules in preparation for strong aux typing becoming the default.
Passes toolstash-check on s390x.
Change-Id: Id585b0db492780737818024e1b22b4837435b525
Reviewed-on: https://go-review.googlesource.com/c/go/+/250558
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
