Use the libc fcntl (via syscall.fcntl) on aix and solaris like it is
already done for darwin.

For the syscall-based fcntl implementation use FcntlSyscall from
internal/syscall/unix in order to get fcntl64 on 32-bit Linux
systems.

On aix, fcntl with F_DUPFD_CLOEXEC is not supported. Thus, defined
F_DUPFD_CLOEXEC = 0 in the syscall package and check its value before
calling fcntl(fd, syscall.F_DUPFD_CLOEXEC, 0).

On js/wasm, fcntl is not supported thus let its implementation return
ENOSYS directly.

Updates #36211

Change-Id: I96a2ea79e5c4eed2fefd94d0aefd72c940825682
Reviewed-on: https://go-review.googlesource.com/c/go/+/212278
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

On aix and solaris (like on darwin) use libc fcntl to implement
IsNonblock instead of Syscall(SYS_FCNTL, ...) which isn't supported.

Change-Id: I989b02aa0c90b7e2dae025572867dda277fef8be
Reviewed-on: https://go-review.googlesource.com/c/go/+/212600
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: I25fbd63f10ea9892589ad44cc45761926aff0648
Reviewed-on: https://go-review.googlesource.com/c/go/+/212841Reviewed-by: Ian Lance Taylor <iant@golang.org>

Use fcntl64Syscall in forkAndExecInChild1 to get fcntl64 on 32-bit Linux
systems.

Updates #36211

Change-Id: Id0e34359256beace970e72102fdace7a987ff2b0
Reviewed-on: https://go-review.googlesource.com/c/go/+/212598
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

This change makes it so that we check whether scavAddr is actually
mapped before trying to look at the summary for the fast path, since we
may segfault if that that part of the summary is not mapped in.
Previously this wasn't a problem because we would conservatively map
all memory for the summaries between the lowest mapped heap address and
the highest one.

This change also adds a test for this case.

Change-Id: I2b1d89b5e044dce81745964dfaba829f4becdc57
Reviewed-on: https://go-review.googlesource.com/c/go/+/212637
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

Fixes #36245

Change-Id: I10ce50b0cc28b15f4e7be85b8f12cf9d0e4fac96
Reviewed-on: https://go-review.googlesource.com/c/go/+/212404
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>

Updates #36281

Change-Id: I3c4487caaf47566212dc62322b2e884e695ea7f1
Reviewed-on: https://go-review.googlesource.com/c/go/+/212657Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This change disables pageAlloc tests on OpenBSD in short mode because
pageAlloc holds relatively large virtual memory reservations and we make
two during the pageAlloc tests. The runtime may also be carrying one
such reservation making the virtual memory requirement for testing the
Go runtime three times as much as just running a Go binary.

This causes problems for folks who just want to build and test Go
(all.bash) on OpenBSD but either don't have machines with at least 4ish
GiB of RAM (per-process virtual memory limits are capped at some
constant factor times the amount of physical memory) or their
per-process virtual memory limits are low for other reasons.

Fixes #36210.

Change-Id: I8d89cfde448d4cd2fefff4ad6ffed90de63dd527
Reviewed-on: https://go-review.googlesource.com/c/go/+/212177
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>

Use FcntlSyscall from internal/syscall/unix to get fcntl64 on 32-bit
Linux systems.

Updates #36211

Change-Id: If48a6e09606ca9f7f6e22f3e8dc9a25fb3ccaf65
Reviewed-on: https://go-review.googlesource.com/c/go/+/212537
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Package name and documentation link were wrong.

Change-Id: I274906afc3cf7a3d88e3da76549cd6ab008fd0c7
Reviewed-on: https://go-review.googlesource.com/c/go/+/212538Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fix a typo DNS name, it should be [onion.vegetables.com](http://onion.vegetables.com/)

Change-Id: I4122a2305b8f5e774a834651e70c75b54e9386bd
GitHub-Last-Rev: 9907897944275c5f8c54c79667cbb1ef474539de
GitHub-Pull-Request: golang/go#36270
Reviewed-on: https://go-review.googlesource.com/c/go/+/212410Reviewed-by: Ian Lance Taylor <iant@golang.org>

Updates #27532

Change-Id: Ib3e44ec524ed20bbfbbaf40df22cec335460f3ef
Reviewed-on: https://go-review.googlesource.com/c/go/+/204629
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

Based on riscv-go port.

Updates #27532

Change-Id: I5e7f45955e1dfdb9d09cc6a4e6f3ce81216d411d
Reviewed-on: https://go-review.googlesource.com/c/go/+/204628Reviewed-by: Cherry Zhang <cherryyz@google.com>

Also provide REG_LR to more clearly define the link register.

Based on the riscv-go port.

Updates #27532

Change-Id: I0805f373682f93b3918a01c21d4ef34eb3817c75
Reviewed-on: https://go-review.googlesource.com/c/go/+/204627Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Patch up runtime testing to use the libc fcntl function on Darwin,
which is what we should be doing anyhow. This is similar to how
we handle fcntl on AIX and Solaris.

Fixes #36211

Change-Id: I47ad87e11df043ce21496a0d59523dad28960f76
Reviewed-on: https://go-review.googlesource.com/c/go/+/212299
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>

The doc for testing.T and testing.B said that both test and benchmark
logs are printed to stderr, but in reality that wasn't the case.

CL 24311 fixed the doc for T, this change fixes it for B.

Fixes #36257

Change-Id: I0ff77ff44608f60320a1565b371c81e96039e71c
Reviewed-on: https://go-review.googlesource.com/c/go/+/212457Reviewed-by: Gabriel Aszalos <gabriel.aszalos@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Gabriel Aszalos <gabriel.aszalos@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This is based on reading through every commit message to runtime and
cmd/{compile,link,internal,asm} since Go 1.13.

Change-Id: I253b1a70ed265f15180fa20c191ceeafa6612ac4
Reviewed-on: https://go-review.googlesource.com/c/go/+/211977Reviewed-by: Matthew Dempsky <mdempsky@google.com>

The test for issue 8945 was marked to only run on gccgo, but there was
no reason for that. It broke for gccgo using GCC 10, because GCC 10
defaults to -fno-common. Make the test run on gc, and split it into
test.go and testx.go to make it work with GCC 10.

The test for issue 9026 used two identical structs which GCC 10 turns
into the same type. The point of the test is not that the structs are
identical, but that they are handled in a particular order. So make
them different.

Updates #8945
Updates #9026

Change-Id: I000fb02f88f346cfbbe5dbefedd944a2c64e8d8e
Reviewed-on: https://go-review.googlesource.com/c/go/+/211217
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>

nanotime1 and walltime1 do not preserve BP on linux amd64. Previously, this
did not cause a problem, because nanotime/walltime do preserve the BP. But now
with mid-stack inlining, nanotime/walltime are usually inlined, so BP is not
preserved. So, the BP is now wrong in any function after a call to
nanotime()/walltime() on amd64. That means the frame pointer on the stack can
be wrong for any further function call made after the nanotime() call (notably
runtime.main and various GC functions). [386 doesn't use framepointer.]

Fix is to set a frame size of 8 for nanotime1 and walltime1, which means the
standard prolog/epilog that saves/restore BP in the stack frame is added.

I noticed this while investigating issue 16638 (use frame pointers for
runtime.Callers). This change would needed for progress on that issue (which
doesn't have a high priority). Verified that this fix works/is useful for issue
16638.

Change-Id: I19e19ef2c1a517d737a34928baae034f2eb0b2c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/212079
Run-TryBot: Dan Scales <danscales@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The documentation for RecentTag indicates that it returns an actual
tag, not a canonicalized prefix+version blob equivalent to a tag,
so the canonicalization due to semver.Max seems like a bug here.

Fortunately, RecentTag is not currently ever actually used as a tag,
so the removal of metadata does not result in a user-facing bug.
Nonetheless, it may be a subtle source of confusion for maintainers
in the future.

Updates #32700

Change-Id: I525423c1c0c7ec7c36c09e53b180034474f74e5a
Reviewed-on: https://go-review.googlesource.com/c/go/+/212202
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

I noticed the missing diagnostic when writing a regression test for #33795.

Change-Id: Ic3249436a6109d71f9ff720b7096f9b872f6a94b
Reviewed-on: https://go-review.googlesource.com/c/go/+/212201
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

Updates #32700
Fixes #33795

Change-Id: I16897a0a2f3aa2f0b0bf8cf8252f3f39eef2e7ba
Reviewed-on: https://go-review.googlesource.com/c/go/+/212200
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The 'go' command normally requires the 'go.mod' files for replacement
modules to have a major version compatible with the module they are
replacing.

However, prior to CL 206761, the 'go' command erroneously allowed
unversioned paths (which imply major version 0 or 1) to replace
'gopkg.in' paths with any major-version suffix.

An analysis of proxy.golang.org suggests that these replacements,
while uncommon, are not unheard-of. Rather than breaking the modules
that rely on them, we will continue to allow the erroneous replacement
paths for this particular pairing.

Updates #34254

Change-Id: Icb4e745981803edaa96060f17a8720a058219ab1
Reviewed-on: https://go-review.googlesource.com/c/go/+/212105
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

When the -modfile flag is in use (either explicitly or from GOFLAGS),
'go list -m' will now print the effective go.mod file for the main
module in the GoMod field in -f or -json output.

Fixes #36220
Updates #34506

Change-Id: I89c2ee40f20e07854bb37c6e4e13eeea0cce7b0d
Reviewed-on: https://go-review.googlesource.com/c/go/+/212100
Run-TryBot: Jay Conrod <jayconrod@google.com>
Reviewed-by: Bryan C. Mills <bcmills@google.com>

Fixes #29100

Change-Id: I195191aad825266ab55d38addef9d662cfc72dff
Reviewed-on: https://go-review.googlesource.com/c/go/+/212099
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

The recently added slice function used indirectInterface, but then
forgot to actually call reflect.Value.Slice on its result. Calling the
Slice method on the original Value without indirectInterface would
result in a panic, if our slice was indeed behind an interface.

Fix that, and add test cases for all three built-in functions that work
with slices.

Fixes #36199.

Change-Id: I9a18f4f604a3b29967eefeb573f8960000936b88
Reviewed-on: https://go-review.googlesource.com/c/go/+/211877
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

Fixes #36190
Fixes #36191

Change-Id: I1213ef37b6595af63dbe202a8ade65741caf1356
Reviewed-on: https://go-review.googlesource.com/c/go/+/212001Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

We don't asynchronously preempt if we are in the runtime. We do
this by checking the function name. However, it failed to take
inlining into account. If a runtime function gets inlined into
a non-runtime function, it can be preempted, and bad things can
happen. One instance of this is dounlockOSThread inlined into
UnlockOSThread which is in turn inlined into a non-runtime
function.

Fix this by using the innermost frame's function name.

Change-Id: Ifa036ce1320700aaaefd829b4bee0d04d05c395d
Reviewed-on: https://go-review.googlesource.com/c/go/+/211978
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Change-Id: I9519659983de23f43ff0e05cffd336d8bc351400
Reviewed-on: https://go-review.googlesource.com/c/go/+/211758Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Alexander Rakoczy <alex@golang.org>

Inconsistency between cmd/doc/main.go and cmd/go/internal/doc/doc.go

Fixes #34976

Change-Id: I429200f9305d473edb4505216bb4840ba92af818
Reviewed-on: https://go-review.googlesource.com/c/go/+/201857
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>

Fixes #36169

Change-Id: Ib9a53fdb0112635b53be38d6818834dd1775e70c
Reviewed-on: https://go-review.googlesource.com/c/go/+/211698
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

This makes the check the same as the one in the tests vet check.
It's safer to check the number of arguments rather than for a nil
slice.

Change-Id: I8e04e9c612573f334770c1c4245238649656c6e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/211598
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

Fixes #36168

Change-Id: If2b7368671e83657a3a74dd030e66e7c68bf2361
Reviewed-on: https://go-review.googlesource.com/c/go/+/211657Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

The comment "If the name is the name of this template, overwrite this template."
is incorrect and should be "is not" instead. This comment is no longer
required once the docs are updated to mention this behaviour instead.

Fixes #34695

Change-Id: I773495b2194d7bb7619b13c1a28cbc76e8f69aac
Reviewed-on: https://go-review.googlesource.com/c/go/+/199139Reviewed-by: Rob Pike <r@golang.org>

Fixes #35627

Change-Id: I0c5fed46a69a9663e46a9414468ec610063ea05a
Reviewed-on: https://go-review.googlesource.com/c/go/+/207849Reviewed-by: Rob Pike <r@golang.org>

This page has moved to the x/website repo in CL 211300 (commit
golang/website@3c8b7f99cadaa000e642595d0fabcd9ac496f335).
Remove the old copy in this repo since it's no longer used.

Updates #29206

Change-Id: I8b3396d9e42d1e7262a8cde9577962d33b215836
Reviewed-on: https://go-review.googlesource.com/c/go/+/211301Reviewed-by: Filippo Valsorda <filippo@golang.org>

Change-Id: I14b1a21a8639b3241326e74ab6152673d5d71243
Reviewed-on: https://go-review.googlesource.com/c/go/+/211517
Run-TryBot: Alexander Rakoczy <alex@golang.org>
Run-TryBot: Carlos Amedee <carlos@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

Systems where PowerRegisterSuspendResumeNotification returns ERROR_
FILE_NOT_FOUND are also systems where nanotime() is on "program time"
rather than "real time".  The chain for this is:

powrprof.dll!PowerRegisterSuspendResumeNotification ->
  umpdc.dll!PdcPortOpen ->
    ntdll.dll!ZwAlpcConnectPort("\\PdcPort") ->
      syscall -> ntoskrnl.exe!AlpcpConnectPort

Opening \\.\PdcPort fails with STATUS_OBJECT_NAME_NOT_FOUND when pdc.sys
hasn't been initialized. Pdc.sys also provides the various hooks for
sleep resumption events, which means if it's not loaded, then our "real
time" timer is actually on "program time". Finally STATUS_OBJECT_NAME_
NOT_FOUND is passed through RtlNtStatusToDosError, which returns ERROR_
FILE_NOT_FOUND. Therefore, in the case where the function returns ERROR_
FILE_NOT_FOUND, we don't mind, since the timer we're using will
correspond fine with the lack of sleep resumption notifications. This
applies, for example, to Docker users.

Fixes #35447
Fixes #35482

Change-Id: I9e1ce5bbc54b9da55ff7a3918b5da28112647eee
Reviewed-on: https://go-review.googlesource.com/c/go/+/208317Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

An Example function with arguments is not a valid example to be
run with go test. Don't return those functions from Examples. This
means that some functions that were previously showing up in
Examples will no longer show up. But those functions were not being
tested properly so the fact that they were showing up is misleading.

This fixes an issue where a confusing compiler error was showing
up when running go test on a file with an invalid example. While
that issue could have been fixed by returning an error, this is
more consistent with the behavior of go/doc.Examples, and the tests
checker in vet will catch this issue.

Fixes #35284

Change-Id: I2101a7d19f38522ef9c2e50967f9cfb30d28c730
Reviewed-on: https://go-review.googlesource.com/c/go/+/211357
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

Fixes #35753

Change-Id: I38674c59c601785eb25b778dc25efdb92231dd9b
Reviewed-on: https://go-review.googlesource.com/c/go/+/208223
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>