Russ Cox [Thu, 12 Jan 2023 14:30:38 +0000 (09:30 -0500)]
runtime: replace panic(nil) with panic(new(runtime.PanicNilError))
Long ago we decided that panic(nil) was too unlikely to bother
making a special case for purposes of recover. Unfortunately,
it has turned out not to be a special case. There are many examples
of code in the Go ecosystem where an author has written panic(nil)
because they want to panic and don't care about the panic value.
Using panic(nil) in this case has the unfortunate behavior of
making recover behave as though the goroutine isn't panicking.
As a result, code like:
looks like it guarantees that call2 has been run any time f returns,
but that turns out not to be strictly true. If call1 does panic(nil),
then f returns "successfully", having recovered the panic, but
without calling call2.
which defeats nearly the whole point of recover. No one does this,
with the result that almost all uses of recover are subtly broken.
One specific broken use along these lines is in net/http, which
recovers from panics in handlers and sends back an HTTP error.
Users discovered in the early days of Go that panic(nil) was a
convenient way to jump out of a handler up to the serving loop
without sending back an HTTP error. This was a bug, not a feature.
Go 1.8 added panic(http.ErrAbortHandler) as a better way to access the feature.
Any lingering code that uses panic(nil) to abort an HTTP handler
without a failure message should be changed to use http.ErrAbortHandler.
Programs that need the old, unintended behavior from net/http
or other packages can set GODEBUG=panicnil=1 to stop the run-time error.
Uses of recover that want to detect panic(nil) in new programs
can check for recover returning a value of type *runtime.PanicNilError.
Because the new GODEBUG is used inside the runtime, we can't
import internal/godebug, so there is some new machinery to
cross-connect those in this CL, to allow a mutable GODEBUG setting.
That won't be necessary if we add any other mutable GODEBUG settings
in the future. The CL also corrects the handling of defaulted GODEBUG
values in the runtime, for #56986.
Russ Cox [Mon, 16 Jan 2023 13:02:34 +0000 (08:02 -0500)]
cmd/go/internal/modindex: remove copy of build.Package
modindex defines its own type Package that must be exactly the
same as build.Package (there are conversions between them).
The normal reason to do this is to provide a different method set,
but there aren't any different methods. And if we needed to do that,
we could write
type Package build.Package
instead of repeating the struct definition. Remove the type entirely
in favor of direct use of build.Package.
This makes the modindex package not break when fields are
added to go/build.Package.
Bryan C. Mills [Tue, 10 Jan 2023 20:59:12 +0000 (15:59 -0500)]
cmd/go: shorten TestScript/test_shuffle and skip it in short mode
test_shuffle was added in CL 310033. It takes about 4½ seconds on my
workstation prior to this CL, most of which is spent linking and
running test binaries in 'go test'.
We can reduce that time somewhat (to 3¾ seconds) by simply running the
test fewer times (cases of 'off', 'on', positive, zero, and negative
values seem sufficient), but we should also avoid that linking
overhead at all in short mode.
Bryan C. Mills [Tue, 10 Jan 2023 17:59:16 +0000 (12:59 -0500)]
cmd/go/internal/lockedfile: avoid failing tests due to arbitrary timeouts
The mustBlock helper returns a function that verifies that the blocked
operation does eventually complete. However, it used an arbitrary
10-second timeout in place of “eventually”.
Since the test is checking a synchronization library, bugs are likely
to manifest as deadlocks. It may be useful to log what operation is in
flight if such a deadlock occurs; however, since we can't bound how
long a “reasonable” operation should take, the log message should only
be informational — it should not cause the test to fail.
While we're here, let's also set a better example by not leaking
time.After timers in the tests..
This uses the new Cancel and WaitDelay fields of os/exec.Cmd
(added in #50436) to interrupt or kill the 'hg serve' command
when its incoming http.Request is canceled.
This should keep the vcweb hg handler from getting stuck if 'hg serve'
hangs after the request either completes or is canceled.
Bryan C. Mills [Thu, 5 Jan 2023 19:00:25 +0000 (14:00 -0500)]
net: delete TestTCPSelfConnect
This test is flaky, apparently due to a typo'd operator in CL 21447
that causes it to compare “same port OR IP” instead of
“same port AND IP”.
If we merely fixed the comparison, the test would hopefully stop being
flaky itself, but we would still be left with another problem:
repeatedly dialing a port that we believe to be unused can interfere
with other tests, which may open the previously-unused port and then
attempt a single Dial and expect it to succeed. Arbitrary other Dial
calls for that port may cause the wrong connection to be accepted,
leading to spurious test failures.
Moreover, the test can be extremely expensive for the amount of data
we hope to get from it, depending on the system's port-reuse
algorithms and dial implementations. It is already scaled back by up
to 1000x on a huge number of platforms due to latency, and may even be
ineffective on those platforms because of the arbitrary 1ms Dial
timeout. And the incremental value from it is quite low, too: it tests
the workaround for what is arguably a bug in the Linux kernel, which
ought to be fixed (and tested) upstream instead of worked around in
every open-source project that dials local ports.
Instead of trying to deflake this test, let's just get rid of it.
Bryan C. Mills [Thu, 8 Dec 2022 13:44:51 +0000 (08:44 -0500)]
runtime: remove arbitrary GOARCH constraints in finalizer tests
These tests were only run on GOARCH=amd64, but the rationale given in
CL 11858043 was GC precision on 32-bit platforms. Today, we have far
more 64-bit platforms than just amd64, and I believe that GC precision
on 32-bit platforms has been substantially improved as well.
The GOARCH restriction seems unnecessary.
Bryan C. Mills [Tue, 13 Dec 2022 19:19:59 +0000 (14:19 -0500)]
os: deflake TestPipeEOF and TestFifoEOF
- Consolidate the two test bodies as one helper function.
- Eliminate arbitrary timeout.
- Shorten arbitrary sleeps in short mode.
- Simplify goroutines.
- Mark the tests as parallel.
Fixes #36107.
Updates #24164.
Change-Id: I14fe4395963a7256cb6d2d743d348a1ade077d5b
Reviewed-on: https://go-review.googlesource.com/c/go/+/457336 Reviewed-by: Rob Pike <r@golang.org>
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
Joe Tsai [Wed, 18 Jan 2023 18:22:54 +0000 (10:22 -0800)]
time: revert strict parsing of RFC 3339
CL 444277 fixed Time.UnmarshalText and Time.UnmarshalJSON to properly
unmarshal timestamps according to RFC 3339 instead of according
to Go's bespoke time syntax that is a superset of RFC 3339.
However, this change seems to have broken an AWS S3 unit test
that relies on parsing timestamps with single digit hours.
It is unclear whether S3 emits these timestamps in production or
whether this is simply a testing artifact that has been cargo culted
across many code bases. Either way, disable strict parsing for now
and re-enable later with better GODEBUG support.
Updates #54580
Change-Id: Icced2c7f9a6b2fc06bbd9c7e90f90edce24c2306
Reviewed-on: https://go-review.googlesource.com/c/go/+/462286 Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Russ Cox <rsc@golang.org> Reviewed-by: Russ Cox <rsc@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Bryan C. Mills [Wed, 18 Jan 2023 15:08:34 +0000 (10:08 -0500)]
cmd/go: do not attempt to install cmd/addr2line in TestScript/mod_outside
Tests must not write to GOROOT: it might not writable (for example, if
it is owned by root and the user is non-root), and in general we can't
assume that the configuration in which the test is run matches the
configuration with which the installed tools were built.
In this specific case, CL 454836 (for #57007) installs 'cmd' with
CGO_ENABLED=0, but most builders still run the tests with CGO_ENABLED
unset.
Ian Lance Taylor [Wed, 18 Jan 2023 00:14:05 +0000 (16:14 -0800)]
misc/reboot: overlay $GOROOT/lib in temporary goroot
This fixes the test after CL 455357, which builds the time/tzdata file
from $GOROOT/lib/time/zoneinfo.zip.
Change-Id: I0c5afa6521b58dd3b57c3b4c3c704a622b846382
Reviewed-on: https://go-review.googlesource.com/c/go/+/462279
Run-TryBot: Ian Lance Taylor <iant@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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Russ Cox [Sat, 14 Jan 2023 21:40:22 +0000 (16:40 -0500)]
cmd/go: introduce GOROOT/go.env and move proxy/sumdb config there
Various Linux distributions edit cmd/go/internal/cfg/cfg.go to change
the default settings of GOPROXY and GOSUMDB. Make it possible for
them to do this without editing the go command source code by
introducing GOROOT/go.env and moving those defaults there.
With the upcoming changes for reproducible builds (#24904),
this should mean that Linux distributions distribute binaries
that are bit-for-bit identical to the Go distribution binaries,
even when rebuilding the distribution themselves.
Russ Cox [Fri, 2 Dec 2022 15:39:30 +0000 (10:39 -0500)]
cmd/dist: make toolchain build reproducible
- Build cmd with CGO_ENABLED=0. Doing so removes the C compiler
toolchain from the reproducibility perimeter and also results in
cmd/go and cmd/pprof binaries that are statically linked,
so that they will run on a wider variety of systems.
In particular the Linux versions will run on Alpine and NixOS
without needing a simulation of libc.so.6.
The potential downside of disabling cgo is that cmd/go and cmd/pprof
use the pure Go network resolver instead of the host resolver on
Unix systems. This means they will not be able to use non-DNS
resolver mechanisms that may be specified in /etc/resolv.conf,
such as mDNS. Neither program seems likely to need non-DNS names
like those, however.
macOS and Windows systems still use the host resolver, which they
access without cgo.
- Build cmd with -trimpath when building a release.
Doing so removes $GOPATH from the file name prefixes stored in the
binary, so that the build directory does not leak into the final artifacts.
- When CC and CXX are empty, do not pick values to hard-code into
the source tree and binaries. Instead, emit code that makes the
right decision at runtime. In addition to reproducibility, this
makes cross-compiled toolchains work better. A macOS toolchain
cross-compiled on Linux will now correctly look for clang,
instead of looking for gcc because it was built on Linux.
- Convert \ to / in file names stored in .a files.
These are converted to / in the final binaries, but the hashes of
the .a files affect the final build ID of the binaries. Without this
change, builds of a Windows toolchain on Windows and non-Windows
machines produce identical binaries except for the input hash part
of the build ID.
- Due to the conversion of \ to / in .a files, convert back when
reading inline bodies on Windows to preserve output file names
in error messages.
Combined, these four changes (along with Go 1.20's removal of
installed pkg/**.a files and conversion of macOS net away from cgo)
make the output of make.bash fully reproducible, even when
cross-compiling: a released macOS toolchain built on Linux or Windows
will contain exactly the same bits as a released macOS toolchain
built on macOS.
The word "released" in the previous sentence is important.
For the build IDs in the binaries to work out the same on
both systems, a VERSION file must exist to provide a consistent
compiler build ID (instead of using a content hash of the binary).
Russ Cox [Fri, 9 Dec 2022 20:09:46 +0000 (15:09 -0500)]
make.bash, make.rc: fix GOROOT detection when GOEXPERIMENT is set
We need to clear GOEXPERIMENT any time we are invoking a bootstrap
toolchain. One line missed the clearing of GOEXPERIMENT.
There were three different lines using different syntaxes and subtly
different sets of variables being cleared, so hoist them into a function
so it's all in one place.
Russ Cox [Tue, 6 Dec 2022 04:39:49 +0000 (23:39 -0500)]
time/tzdata: generate zip constant during cmd/dist
We have a make.bash-time generation capability,
so use it to generate the embedded zip file for time/tzdata.
This is one less file to try to review in CLs like CL 455356.
For #22487.
Fixes #43350.
Change-Id: I2fcd0665fa0b1c830baec5fb4cd714483fea25a4
Reviewed-on: https://go-review.googlesource.com/c/go/+/455357
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Russ Cox <rsc@golang.org> Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Auto-Submit: Russ Cox <rsc@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Russ Cox [Fri, 13 Jan 2023 15:21:56 +0000 (10:21 -0500)]
cmd/go: do not confuse files for standard library packages
I often create dummy files holding various data named things like 'z'.
If a file (not directory) GOROOT/src/z exists, it confuses cmd/go into
thinking z is a standard library package, which breaks the test
Script/mod_vendor.
This CL fixes internal/goroot to only report that something is a standard
library package when a directory with that name exists, not just a file.
Matthew Dempsky [Tue, 17 Jan 2023 18:59:25 +0000 (10:59 -0800)]
cmd/compile: fix static init inlining for hidden node fields
Unified IR added several new IR fields for holding *runtime._type
expressions. To avoid throwing off any frontend semantics
(particularly inlining cost heuristics), they were marked as
`mknode:"-"` so that code wouldn't visit them.
Unfortunately, this has a bad interaction with the static init
inlining optimization, because the latter relies on ir.EditChildren to
substitute all parameters. This potentially includes dictionary
parameters, which can appear within the new RType fields.
This CL adds a new ir.EditChildrenWithHidden function that also edits
these fields, and switches staticinit to use it. Longer term, we
should unhide the RType fields so that ir.EditChildren visits them
normally, but that's scarier so late in the release cycle.
Fixes #57778.
Change-Id: I98c1e8cf366156dc0c81a0cb79029cc5e59c476f
Reviewed-on: https://go-review.googlesource.com/c/go/+/461686
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Keith Randall <khr@google.com>
Robert Griesemer [Wed, 11 Jan 2023 17:17:55 +0000 (09:17 -0800)]
go/types, types2: factor out position comparison, share more code
This CL introduces the new files util.go and util_test.go for both
type checkers; these files factor out functionality that is different
between the type checkers so that more code (that is otherwise mostly
the same) can be generated.
With cmpPos/CmpPos factored out, go/types/scope.go can now be generated.
Change-Id: I35f67e53d83b3c5086a559b1e826db83d38ee217
Reviewed-on: https://go-review.googlesource.com/c/go/+/461596
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com> Reviewed-by: Robert Findley <rfindley@google.com>
Robert Griesemer [Mon, 9 Jan 2023 21:02:08 +0000 (13:02 -0800)]
go/types: make tracing configurable (matching types2)
This CL replaces the internal trace flag with Config.trace.
While unexported, it can still be set for testing via reflection.
The typical use is for manual tests, where -v (verbose) turns on
tracing output. Typical use:
go test -run Manual -v
This change makes go/types match types2 behavior.
Change-Id: I22842f4bba8fd632efe5929c950f4b1cab0a8569
Reviewed-on: https://go-review.googlesource.com/c/go/+/461081
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> Reviewed-by: Robert Findley <rfindley@google.com>
Robert Griesemer [Thu, 1 Dec 2022 22:29:11 +0000 (14:29 -0800)]
go/types, types2: do not abort constraint type inference eagerly
During constraint type inference, unification may fail because it
operates with limited information (core types) even if the actual
type argument satisfies the type constraint in question.
On the other hand, it is safe to ignore failing unification during
constraint type inference because if the failure is true, an error
will be reported when checking instantiation.
Fixes #53650.
Change-Id: Ia76b21ff779bfb1282c1c55f4174847b29cc6f3a
Reviewed-on: https://go-review.googlesource.com/c/go/+/454655
Auto-Submit: Robert Griesemer <gri@google.com>
Run-TryBot: Robert Griesemer <gri@google.com> Reviewed-by: Robert Griesemer <gri@google.com> Reviewed-by: Robert Findley <rfindley@google.com>
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Robert Griesemer [Fri, 9 Dec 2022 00:20:37 +0000 (16:20 -0800)]
go/types, types2: distinguish between substring and regexp error patterns
Use ERROR for substrings, and ERRORx for regexp error patterns.
Correctly unquote patterns for ERROR and ERRORx.
Adjust all tests in internal/types/testdata and locally as needed.
The changes to internal/types/testdata were made through
repeated applications of regexpr find/replace commands
and manual cleanups.
Fixes #51006.
Change-Id: Ib9ec5001243b688bf5aee56b7d4105fb55999ab4
Reviewed-on: https://go-review.googlesource.com/c/go/+/455755 Reviewed-by: Robert Griesemer <gri@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Robert Findley <rfindley@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
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Robert Griesemer [Tue, 6 Dec 2022 22:43:39 +0000 (14:43 -0800)]
internal/types: consistently use double quotes around ERROR patterns
Before matching the pattern, the double quotes are simply stripped
(no Go string unquoting) for now. This is a first step towards use
of proper Go strings as ERROR patterns.
The changes were obtained through a couple of global regexp
find/replace commands:
followed up by manual fixes where multiple "/* ERROR"-style
errors appeared on the same line (in that case, the first
regexp matches the first and last ERROR).
For #51006.
Change-Id: Ib92c2d5e339075aeec1ea74c339b5fecf953d1a0
Reviewed-on: https://go-review.googlesource.com/c/go/+/455718
Auto-Submit: Robert Griesemer <gri@google.com> Reviewed-by: Robert Griesemer <gri@google.com>
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Robert Griesemer [Thu, 8 Dec 2022 04:40:37 +0000 (20:40 -0800)]
go/types: use commentMap to collect error comments
Adjust the testFiles function to use the new commentMap
function. This makes it possible for testFiles to match
the types2.TestFiles logic more closely.
For #51006.
Change-Id: I6c5ecbeb86d095404ec04ba4452fb90d404b8280
Reviewed-on: https://go-review.googlesource.com/c/go/+/456137 Reviewed-by: Robert Findley <rfindley@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@google.com>
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Robert Griesemer [Thu, 8 Dec 2022 16:29:14 +0000 (08:29 -0800)]
go/types: add commentMap and test
This adds the (adjusted) syntax.CommentMap function and corresponding
test to the types_test package so that we can use it for collecting
ERROR comments in the next CL.
For #51006.
Change-Id: I63ce96e7394c28c02d5a292250586cc49c1f6e19
Reviewed-on: https://go-review.googlesource.com/c/go/+/456125 Reviewed-by: Robert Findley <rfindley@google.com>
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Cherry Mui [Tue, 17 Jan 2023 19:22:33 +0000 (14:22 -0500)]
internal/goversion: update Version to 1.21
This is the start of the Go 1.21 development cycle, so update the
Version value accordingly. It represents the Go 1.x version that
will soon open up for development (and eventually become released).
For #40705.
For #57736.
Change-Id: I31b739f632bdc8d14f46560e0e5bf333fb8e7740
Reviewed-on: https://go-review.googlesource.com/c/go/+/462456 Reviewed-by: Carlos Amedee <carlos@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Cherry Mui <cherryyz@google.com>
We need to avoid nospill registers at this point in regalloc.
Make sure that we don't restrict our register set to avoid registers
desired by other instructions, if the resulting set includes only
nospill registers.
Fixes #57846
Change-Id: I05478e4513c484755dc2e8621d73dac868e45a27
Reviewed-on: https://go-review.googlesource.com/c/go/+/461685 Reviewed-by: Keith Randall <khr@google.com>
Run-TryBot: Keith Randall <khr@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com>
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fangguizhen [Tue, 17 Jan 2023 16:37:42 +0000 (16:37 +0000)]
strings: remove redundant symbols
Change-Id: Ie3fe0274288d6cb6303acdcec1340c480e5c0b20
GitHub-Last-Rev: ce9d44619e970b1319fbccf3aace1ddf719bcec1
GitHub-Pull-Request: golang/go#57848
Reviewed-on: https://go-review.googlesource.com/c/go/+/462277
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Than McIntosh [Fri, 13 Jan 2023 21:46:49 +0000 (16:46 -0500)]
cmd/go: include coverage build flags for "go list"
This patch ensures that the go command's "list" subcommand accepts
coverage-related build options, which were incorrectly left out when
"go build -cover" was rolled out. This is needed in order to do things
like check the staleness of an installed cover-instrumented target.
Filippo Valsorda [Wed, 4 Jan 2023 20:51:50 +0000 (21:51 +0100)]
crypto/x509: clarify that CheckSignatureFrom and CheckSignature are low-level APIs
In particular, CheckSignatureFrom just can't check the path length
limit, because it might be enforced above the parent.
We don't need to document the supported signature algorithms for
CheckSignatureFrom, since we document at the constants in what contexts
they are allowed and not. That does leave CheckSignature ambiguous,
though, because that function doesn't have an explicit context.
Russ Cox [Sat, 14 Jan 2023 20:08:49 +0000 (15:08 -0500)]
cmd/go: document GODEBUG=installgoroot=all
At the moment the only documentation is the release notes,
but everything mentioned in the release notes should have
proper documentation separate from them.
Russ Cox [Tue, 17 Jan 2023 14:21:43 +0000 (09:21 -0500)]
doc/go1.20: remove mention of arena goexperiment
The arena goexperiment contains code used inside Google in very
limited use cases that we will maintain, but the discussion on #51317
identified serious problems with the very idea of adding arenas to the
standard library. In particular the concept tends to infect many other
APIs in the name of efficiency, a bit like sync.Pool except more
publicly visible.
It is unclear when, if ever, we will pick up the idea and try to push
it forward into a public API, but it's not going to happen any time
soon, and we don't want users to start depending on it: it's a true
experiment and may be changed or deleted without warning.
The arena text in the release notes makes them seem more official
and supported than they really are, and we've already seen a couple
blog posts based on that erroneous belief. Delete the text to try to
set expectations better.
Archana R [Wed, 11 Jan 2023 17:45:28 +0000 (11:45 -0600)]
runtime: fix performance regression in morestack_noctxt on ppc64
In the fix for 54332 the MOVD R1, R1 instruction was added to
morestack_noctxt function to set the SPWRITE bit. However, the
instruction MOVD R1, R1 results in or r1,r1,r1 which is a special
instruction on ppc64 architecture as it changes the thread priority
and can negatively impact performance in some cases.
More details on such similar nops can be found in Power ISA v3.1
Book II on Power ISA Virtual Environment architecture in the chapter
on Program Priority Registers and Or instructions.
Replacing this by OR R0, R1 has the same affect on setting SPWRITE as
needed by the first fix but does not affect thread priority and
hence does not cause the degradation in performance
Robert Findley [Wed, 11 Jan 2023 19:41:03 +0000 (14:41 -0500)]
go/types, types2: don't look up fields or methods when expecting a type
As we have seen many times, the type checker must be careful to avoid
accessing named type information before the type is fully set up. We
need a more systematic solution to this problem, but for now avoid one
case that causes a crash: checking a selector expression on an
incomplete type when a type expression is expected.
For golang/go#57522
Change-Id: I7ed31b859cca263276e3a0647d1f1b49670023a9
Reviewed-on: https://go-review.googlesource.com/c/go/+/461577
Run-TryBot: Robert Findley <rfindley@google.com>
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Robert Griesemer [Wed, 4 Jan 2023 01:05:53 +0000 (17:05 -0800)]
cmd/compile: better error message for when a type is in a constraint but not the type set
While at it, also remove the word "constraint" in the detail explanation
of an unsatisfied constraint.
Fixes #57500.
Change-Id: I55dae1694de2cfdb434aeba9d4a3530af7aca8f5
Reviewed-on: https://go-review.googlesource.com/c/go/+/460455 Reviewed-by: Robert Findley <rfindley@google.com> Reviewed-by: Ian Lance Taylor <iant@google.com>
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Russ Cox [Wed, 4 Jan 2023 14:21:14 +0000 (09:21 -0500)]
cmd/link, runtime: Apple libc atfork workaround take 3
CL 451735 worked around bugs in Apple's atfork handlers by calling
notify_is_valid_token and xpc_atfork_child at startup, so that init
code that wouldn't be safe in the child process would be warmed up in
the parent process instead, but xpc_atfork_child broke use of the xpc
library in Go programs, and xpc is internally used by various macOS
frameworks (#57263).
CL 459175 reverted that change, and then CL 459176 tried a new
approach: use __fork, which doesn't call any of the atfork handlers at all.
That worked, but an Apple engineer reviewing the change in private
email suggests that since __fork is not public API, it should be avoided.
The same engineer (with access to the source code for the xpc library)
suggests that the breakage in #57263 is caused by xpc_atfork_child
marking the library as unusable, expecting an imminent call to exec,
and that calling xpc_date_create_from_current instead would do the
necessary initialization without marking xpc as unusable.
CL 460475 reverted that change, to prepare for this one.
This CL goes back to the original “call functions to warm things up”
approach, replacing xpc_atfork_child with xpc_date_create_from_current.
The CL also updates cmd/link to use OS and SDK version 10.13.0 for
x86 macOS binaries, up from 10.9.0, also suggested by the Apple engineer.
Combined with the two warmup calls, this makes the fork hangs go away.
The minimum macOS version has been 10.13 High Sierra since Go 1.17,
so there should be no problem with writing that in the binaries too.
Russ Cox [Wed, 4 Jan 2023 14:18:02 +0000 (09:18 -0500)]
runtime: revert use of __fork to work around Apple atfork bugs
An Apple engineer suggests that since __fork is not public API,
it would be better to use a different fix. With the benefit of source code,
they suggest using xpc_date_create_from_current instead of
xpc_atfork_child. The latter sets some flags that disable certain
functionality for the remainder of the process lifetime (expecting exec),
while the former should do the necessary setup.
Reverting the __fork fix in order to prepare a clean fix based
on CL 451735 using xpc_date_create_from_current.
Bryan C. Mills [Tue, 10 Jan 2023 16:29:25 +0000 (11:29 -0500)]
os/exec: avoid leaking an exec.Cmd in TestWaitInterrupt
In CL 436655 I added a GODEBUG setting to this test process to verify
that Wait is eventually called for every exec.Cmd before it becomes
unreachable. However, the cmdHang test helpers in
TestWaitInterrupt/Exit-hang and TestWaitInterrupt/SIGKILL-hang
intentially leak a subprocess in order to simulate a leaky third-party
program, as Go users might encounter in practical use.
To avoid tripping over the leak check, we call Wait on the leaked
subprocess in a background goroutine. Since we expect the process
running cmdHang to exit before its subprocess does, the call to Wait
should have no effect beyond suppressing the leak check.
Keith Randall [Mon, 9 Jan 2023 17:49:32 +0000 (09:49 -0800)]
cmd/compile: prevent IsNewObject from taking quadratic time
As part of IsNewObject, we need to go from the SelectN[0] use of
a call to the SelectN[1] use of a call. The current code does this
by just looking through the block. If the block is very large,
this ends up taking quadratic time.
Instead, prepopulate a map from call -> SelectN[1] user of that call.
That lets us find the SelectN[1] user in constant time.
Fixes #57657
Change-Id: Ie2e0b660af5c080314f4f17ba2838510a1147f9e
Reviewed-on: https://go-review.googlesource.com/c/go/+/461080
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Michael Pratt [Mon, 9 Jan 2023 18:59:54 +0000 (13:59 -0500)]
cmd/compile/internal/pgo: add hint to missing start_line error
Profiles only began adding Function.start_line in 1.20. If it is
missing, add a hint to the error message that they may need to profile a
build of the application built with a newer version of the toolchain.
Technically profiles are not required to come from Go itself (e.g., they
could be converted from perf), but in practice they most likely are.
Fixes #57674.
Change-Id: I87eca126d3fed0cff94bbb8dd748bd4652f88b12
Reviewed-on: https://go-review.googlesource.com/c/go/+/461195
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Ian Lance Taylor [Thu, 5 Jan 2023 02:03:46 +0000 (18:03 -0800)]
runtime: skip TestCgoPprofCallback in short mode, don't run in parallel
Fixes #54778
Change-Id: If9aef0c06b993ef2aedbeea9452297ee9f11fa06
Reviewed-on: https://go-review.googlesource.com/c/go/+/460461 Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
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Austin Clements [Thu, 5 Jan 2023 14:08:25 +0000 (09:08 -0500)]
runtime/pprof: document possibility of empty stacks
I spent quite a while determining the cause of empty stacks in
profiles and reasoning out why this is okay. There isn't a great place
to record this knowledge, but a documentation comment on
appendLocsForStack is better than nothing.
Updates #51550.
Change-Id: I2eefc6ea31f1af885885c3d96199319f45edb4ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/460695 Reviewed-by: Felix Geisendörfer <felix.geisendoerfer@datadoghq.com>
Run-TryBot: Austin Clements <austin@google.com>
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Austin Clements [Wed, 4 Jan 2023 17:31:23 +0000 (12:31 -0500)]
runtime/pprof: improve output of TestLabelSystemstack
The current output of TestLabelSystemstack is a bit cryptic. This CL
improves various messages and hopefully simplifies the logic in the
test.
Simplifying the logic leads to three changes in possible outcomes,
which I verified by running the logic before and after this change
through all 2^4 possibilities (https://go.dev/play/p/bnfb-OQCT4j):
1. If a sample both must be labeled and must not be labeled, the test
now reports that explicitly rather than giving other confusing output.
2. If a sample must not be labeled but is, the current logic will
print two identical error messages. The new logic prints only one.
3. If the test finds no frames at all that it recognizes, but the
sample is labeled, it will currently print a confusing "Sample labeled
got true want false" message. The new logic prints nothing. We've seen
this triggered by empty stacks in profiles.
Fixes #51550. This bug was caused by case 3 above, where it was
triggered by a profile label on an empty stack. It's valid for empty
stacks to appear in a profile if we sample a goroutine just as it's
exiting (and that goroutine may have a profile label), so the test
shouldn't fail in this case.
Change-Id: I1593ec4ac33eced5bb89572a3ba7623e56f2fb3d
Reviewed-on: https://go-review.googlesource.com/c/go/+/460516
Run-TryBot: Austin Clements <austin@google.com> Reviewed-by: Felix Geisendörfer <felix.geisendoerfer@datadoghq.com> Reviewed-by: Michael Pratt <mpratt@google.com>
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Change-Id: I56281eda3b178968fbf104de1f71316c1feac64f
GitHub-Last-Rev: e91c7cee340fadfa32b0c1773e4e5cd1ca567638
GitHub-Pull-Request: golang/go#57669
Reviewed-on: https://go-review.googlesource.com/c/go/+/460767
Run-TryBot: Ian Lance Taylor <iant@golang.org>
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Shengjing Zhu [Thu, 5 Jan 2023 07:00:25 +0000 (15:00 +0800)]
syscall: skip TestUseCgroupFD if cgroupfs not mounted
When building in schroot (for building Debian package),
the cgroupfs is not mounted in schroot (only sysfs is mounted).
Change-Id: Ieddac7b2f334d58d832f5d84d81af812badf3720
Reviewed-on: https://go-review.googlesource.com/c/go/+/460539
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Change-Id: I656ea210d8ef6eaa85245cb8f463f6b4fd67e1a2
GitHub-Last-Rev: 5a93045add2f2a6885b46377c784f665ab465cfd
GitHub-Pull-Request: golang/go#57633
Reviewed-on: https://go-review.googlesource.com/c/go/+/460756 Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Than McIntosh [Thu, 22 Dec 2022 19:10:12 +0000 (14:10 -0500)]
cmd/cover: fix problems with "go test -covermode=atomic sync/atomic"
This patch fixes an elderly bug with "go test -covermode=atomic
sync/atomic". Change the cover tool to avoid adding an import of
sync/atomic when processing "sync/atomic" itself in atomic mode;
instead make direct calls to AddUint32/StoreUint32. In addition,
change the go command to avoid injecting an artificial import of
"sync/atomic" for sync/atomic itself.
Robert Griesemer [Wed, 4 Jan 2023 00:01:49 +0000 (16:01 -0800)]
cmd/compile: use "satisfies" (not "implements") for constraint errors
Per the latest spec, we distinguish between interface implementation
and constraint satisfaction. Use the verb "satisfy" when reporting
an error about failing constraint satisfaction.
This CL only changes error messages. It has no impact on correct code.
Fixes #57564.
Change-Id: I6dfb3b2093c2e04fe5566628315fb5f6bd709f17
Reviewed-on: https://go-review.googlesource.com/c/go/+/460396 Reviewed-by: Robert Griesemer <gri@google.com>
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Roland Illig [Wed, 4 Jan 2023 06:59:03 +0000 (06:59 +0000)]
cmd/gofmt: fix a typo in a comment
Change-Id: I34b2b9f9b70e39c872d5edbbda4de0fe330211f5
GitHub-Last-Rev: 723e36e11ee011c54d3ffc8125d0477c8eed25a0
GitHub-Pull-Request: golang/go#57566
Reviewed-on: https://go-review.googlesource.com/c/go/+/460457
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Dan Peterson [Mon, 5 Sep 2022 17:18:40 +0000 (14:18 -0300)]
.github: suggest using private browsing in pkgsite template
I opened #54872 without considering my browser's extensions and one of
them ended up being the cause of my issue. This seems to be a common
error.
To help that, add a suggestion to use a private/incognito tab/window
to the pkgsite issue template when reproducing issues. This probably
would have been enough for me to figure things out before opening my
issue.
Updates #54872, #47213
Change-Id: Ic61a3462cb902c91554cf9432aaae1222c6a991e
Reviewed-on: https://go-review.googlesource.com/c/go/+/427962
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Xiao Cui [Thu, 29 Dec 2022 00:35:13 +0000 (19:35 -0500)]
doc/go1.20: fix typos
Change-Id: Ie2e583cba9e9bec7d642e323e77fb2d9b05dc7bc
Reviewed-on: https://go-review.googlesource.com/c/go/+/459780 Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Robert Griesemer [Wed, 28 Dec 2022 22:21:50 +0000 (14:21 -0800)]
go/types, types2: use strict comparability for type set intersection
Fixes #57486.
Change-Id: I4b71199a724718886ce6d7a49e96a9ebdcbcf737
Reviewed-on: https://go-review.googlesource.com/c/go/+/459816
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Cherry Mui [Tue, 27 Dec 2022 22:29:28 +0000 (17:29 -0500)]
misc/cgo/testsanitizers: run libfuzzer tests in temp directory
The libFuzzer generated binary by default writes failure input
into the current directory. Set cmd.Dir to the temporary directory
so it won't write to GOROOT when running the test.
Change-Id: I3e4ce7e3f845be5c9f09511c36e7a9a396eafad2
Reviewed-on: https://go-review.googlesource.com/c/go/+/459556 Reviewed-by: Than McIntosh <thanm@google.com>
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Andrey Bozhko [Wed, 21 Dec 2022 22:24:05 +0000 (22:24 +0000)]
testing: rephrase the sentence about naming test files
This updates the explanation about
naming test files to be a little more clear.
Fixes #57389
Change-Id: I9b3a8e2dae5e3ad398b55624e183809b7d90864c
GitHub-Last-Rev: 9ff81b74b201ca032fd373424aa02a3fedaec008
GitHub-Pull-Request: golang/go#57399
Reviewed-on: https://go-review.googlesource.com/c/go/+/458435 Reviewed-by: Ian Lance Taylor <iant@google.com>
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Cherry Mui [Wed, 21 Dec 2022 21:35:57 +0000 (16:35 -0500)]
cmd/link, runtime: use a different section for Go libfuzzer counters
Currently in libfuzzer mode, we put our counters in section
__sancov_cntrs. When linking with C/C++ code that also has fuzzer
counters, apparently the C linker combines our counters and their
counters and registers them together. But in the Go runtime we
also have code to register our counters. So the Go counters ended
up registered twice, causing problems.
Since we already have code to register our counters, put them in
a Go-specific section so it won't be combined with the C counters.
Fixes #57449.
Change-Id: If3d41735124e7e301572d4b7aecf7d057ac134c0
Reviewed-on: https://go-review.googlesource.com/c/go/+/459055 Reviewed-by: Nicolas Hillegeer <aktau@google.com> Reviewed-by: Than McIntosh <thanm@google.com>
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Russ Cox [Thu, 22 Dec 2022 14:44:56 +0000 (09:44 -0500)]
runtime: call __fork instead of fork on darwin
Issues #33565 and #56784 were caused by hangs in the child process
after fork, while it ran atfork handlers that ran into slow paths that
didn't work in the child.
CL 451735 worked around those two issues by calling a couple functions
at startup to try to warm up those child paths. That mostly worked,
but it broke programs using cgo with certain macOS frameworks (#57263).
CL 459175 reverted CL 451735.
This CL introduces a different fix: bypass the atfork child handlers
entirely. For a general fork call where the child and parent are both
meant to keep executing the original program, atfork handlers can be
necessary to fix any state that would otherwise be tied to the parent
process. But Go only uses fork as preparation for exec, and it takes
care to limit what it attempts to do in the child between the fork and
exec. In particular it doesn't use any of the things that the macOS
atfork handlers are trying to fix up (malloc, xpc, others). So we can
use the low-level fork system call (__fork) instead of the
atfork-wrapped one.
The full list of functions that can be called in a child after fork in
exec_libc2.go is:
I disassembled all of these while attached to a hung exec.test binary
and confirmed that nearly all of them are making direct kernel calls,
not using anything that the atfork handler needs to fix up.
The exceptions are ioctl, fcntl, and exit.
The ioctl and fcntl implementations do some extra work around the
kernel call but don't call any other functions, so they should still
be OK. (If not, we could use __ioctl and __fcntl instead, but without
a good reason, we should keep using the standard entry points.)
The exit implementation calls atexit handlers. That is almost
certainly inappropriate in a failed fork child, so this CL changes
that call to __exit on darwin. To avoid making unnecessary changes at
this point in the release cycle, this CL leaves OpenBSD calling plain
exit, even though that is probably a bug in the OpenBSD port
(filed #57446).
Fixes #33565.
Fixes #56784.
Fixes #57263.
Change-Id: I26812c26a72bdd7fcf72ec41899ba11cf6b9c4ab
Reviewed-on: https://go-review.googlesource.com/c/go/+/459176 Reviewed-by: David Chase <drchase@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
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Run-TryBot: Russ Cox <rsc@golang.org>
Russ Cox [Thu, 22 Dec 2022 14:21:03 +0000 (09:21 -0500)]
runtime: revert Apple libc atfork workaround
Revert CL 451735 (1f4394a0c926), which fixed #33565 and #56784
but also introduced #57263.
I have a different fix to apply instead. Since the first fix was
never backported, it will be easiest to backport the new fix
if the new fix is done in a separate CL from the revert.