At least one libc call we make
(res_search, which calls _mdns_query and then mdns_item_call)
pushes a 64 kB stack frame onto the stack.
Then it faults on the guard page.

Use the default system stack size, under the assumption
that the C code being called is compatible with that stack size.

For #31705.

Change-Id: I1b0bfc2e54043c49f0709255988ef920ce30ee82
Reviewed-on: https://go-review.googlesource.com/c/go/+/180779
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #32167

Change-Id: If1277789ac96363430045e73e49d008bdae9be79
GitHub-Last-Rev: 71c9435c8417b19faaf66dc2e08740d7a9c22e3b
GitHub-Pull-Request: golang/go#32171
Reviewed-on: https://go-review.googlesource.com/c/go/+/178397
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #32427

Change-Id: I4b863bd3836067dcc2eb3a9c3a7169656763d003
Reviewed-on: https://go-review.googlesource.com/c/go/+/180438Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

This reverts commit fff4f599.

Reason for revert: Seems to still have issues around GC.

Fixes #32452

Change-Id: Ibe7af629f9ad6a3d5312acd7b066123f484da7f0
Reviewed-on: https://go-review.googlesource.com/c/go/+/180761
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Change-Id: Ibe514058770bd5342e1f344c5b8a9ab1427d5dfe
Reviewed-on: https://go-review.googlesource.com/c/go/+/180297
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

It was rolled back.

Change-Id: I8372bb7e11bab7be242f4af7093a73d2fa093067
Reviewed-on: https://go-review.googlesource.com/c/go/+/180760Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The additions were generated using golang.org/x/build/cmd/relnote.

Change-Id: Ie7322f7d01a2dd4a7bca89b9ef9c1ce93bc2671a
Reviewed-on: https://go-review.googlesource.com/c/go/+/180778Reviewed-by: Bryan C. Mills <bcmills@google.com>

Windows does not have atomic renames; instead, it produces one of a
handful of errors in case a read races with a rename.

CL 180219 added a utility function that retries those errors in most
cases; this change updates the locations that use renameio for writes
to also use the new renameio.ReadFile function for reads.

It remains possible for a renameio.ReadFile to fail with a spurious
ERROR_FILE_NOT_FOUND, but with retries in place for the other errors
(and practical limits on write concurrency) such failures are unlikely
in practice.

Fixes #32188

Change-Id: I78c81051cc871325c1e3229e696b921b0fcd865a
Reviewed-on: https://go-review.googlesource.com/c/go/+/180517
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

ReadFile is a drop-in replacement for ioutil.ReadFile that works
around Windows filesystem flakiness under load.

A followup CL will replace uses of ioutil.ReadFile in cmd/go with this
function.

Updates #32188

Change-Id: I232ba893b132bdc84cd7b0edde436165a69e1aa8
Reviewed-on: https://go-review.googlesource.com/c/go/+/180219
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

Updates #31093

Change-Id: I7962aaca0b012de01768b7b42dc2283d5845eeea
Reviewed-on: https://go-review.googlesource.com/c/go/+/180377
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

Roll back CL 159258 and CL 168337. Those changes broke existing
code. I can't see any way to keep existing code working while also
producing good error messages for types like C.ulong (such as the ones
already tested for in misc/cgo/errors).

This is not an exact roll back because parts of the code have changed
since those CLs.

Updates #29878
Fixes #31093

Change-Id: I56fe76c167ff0ab381ed273b9ca4b952402e1434
Reviewed-on: https://go-review.googlesource.com/c/go/+/180357
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

Roll back CL 161738. That fix changed StripPrefix behavior in the
general case, not just in the situation where where stripping the
prefix from path resulted in the empty string, causing issue #31622.

That kind of change to StripPrefix behavior is not backwards compatible,
and there can be a smaller, more targeted fix for the original issue.

Fixes #31622
Updates #30165

Change-Id: Ie2fcfe6787a32e44f71d564d8f9c9d580fc6f704
Reviewed-on: https://go-review.googlesource.com/c/go/+/180498
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

GOSUMDB and GONOSUMDB are described in detail by
'go help module-auth'. So, this change mentions the two
variables and says to see 'go help module-auth'.

This also adds GONOPROXY to 'go help environment'.

Fixes #32292 and updates #32056.

Change-Id: I2eae0f906a3fbfcb88ad5c8fb4870917d0d7bbcd
Reviewed-on: https://go-review.googlesource.com/c/go/+/179219Reviewed-by: Russ Cox <rsc@golang.org>

When a defer is executed at most once in a function body,
we can allocate the defer record for it on the stack instead
of on the heap.

This should make defers like this (which are very common) faster.

This optimization applies to 363 out of the 370 static defer sites
in the cmd/go binary.

name     old time/op  new time/op  delta
Defer-4  52.2ns ± 5%  36.2ns ± 3%  -30.70%  (p=0.000 n=10+10)

Fixes #6980
Update #14939

Change-Id: I697109dd7aeef9e97a9eeba2ef65ff53d3ee1004
Reviewed-on: https://go-review.googlesource.com/c/go/+/171758
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Some <h3>s were missing ids due to which the anchor links
weren't getting generated.

Fixes #32415

Change-Id: Ica21425c1a7c49735231c1de96b6c77dd594ce64
Reviewed-on: https://go-review.googlesource.com/c/go/+/180397Reviewed-by: Ian Lance Taylor <iant@golang.org>

The example in example_test.go requires that the whole file be
displayed; the addition of ExampleAs meant that only the body of the
package example function was shown, rather than the surrounding context.

This change moves ExampleAs to the file wrap_test.go file, restoring the
package example to its former glory.

Update #31716

Change-Id: Id0ea77bc06023b239a63c1d6a7c8b3c1dae91ce9
Reviewed-on: https://go-review.googlesource.com/c/go/+/179737Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
Reviewed-by: Jean de Klerk <deklerk@google.com>
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #32386

Change-Id: I29ad4113b02264336eebe7865895f07ef386f450
Reviewed-on: https://go-review.googlesource.com/c/go/+/180177
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

ARM64's R19-R29 and F8-F15 are callee saved registers, which
should be saved in the beginning of sigtramp, and restored at
the end.

fixes #31827

Change-Id: I622e03f1a13fec969d3a11b6a303a8a492e02bcd
Reviewed-on: https://go-review.googlesource.com/c/go/+/177045
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

Normally, reflect.makeFuncStub records the context value at a known
point in the stack frame, so that the runtime can get the argument map
for reflect.makeFuncStub from that known location.

This doesn't work for defers or goroutines that haven't started yet,
because they haven't allocated a frame or run an instruction yet. The
argument map must be extracted from the context value. We already do
this for defers (the non-nil ctxt arg to getArgInfo), we just need to
do it for unstarted goroutines as well.

When we traceback a goroutine, remember the context value from
g.sched.  Use it for the first frame we find.

(We never need it for deeper frames, because we normally don't stop at
 the start of reflect.makeFuncStub, as it is nosplit. With this CL we
 could allow makeFuncStub to no longer be nosplit.)

Fixes #25897

Change-Id: I427abf332a741a80728cdc0b8412aa8f37e7c418
Reviewed-on: https://go-review.googlesource.com/c/go/+/180258Reviewed-by: Cherry Zhang <cherryyz@google.com>

Fixes #31857

Change-Id: Ic4afe1262d863112db97794edc1ade20f6926d64
Reviewed-on: https://go-review.googlesource.com/c/go/+/180197Reviewed-by: Jay Conrod <jayconrod@google.com>

When adding coverage counters to a block, the block's statement list is
mutated. CL 77150 removed the part where the mutated list is assigned
back to its parent node; this was confusing ast.Walk, which would then
lose its place and stop walking the current block, dropping counters in
the process.

This change has addCounters make a copy of the list before mutating
it, so that the original list doesn't change under Walk's feet.

Fix #32200

Change-Id: Ia3b67d8cee860ceb7caf8748cb7a80ff9c6276e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/179581Reviewed-by: Rob Pike <r@golang.org>

As js.TypedArray no longer exists, the comment should be updated.

Change-Id: Idd1087c8007afc90307fdd965f28d3be8d8cd73e
Reviewed-on: https://go-review.googlesource.com/c/go/+/180097Reviewed-by: Richard Musiol <neelance@gmail.com>

Change-Id: Ie9fef7767f3263ef7daed8415ab2f59c5377a3cb
GitHub-Last-Rev: a4d13b7452f0fe060cb7575acfc200e3353fdde0
GitHub-Pull-Request: golang/go#32385
Reviewed-on: https://go-review.googlesource.com/c/go/+/180037Reviewed-by: Agniva De Sarker <agniva.quicksilver@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

In module mode, 'go get' should not consider build constraints when
loading packages in order to modify the module graph. With this
change, 'go get' considers all build tags to be true except for
"ignore" and malformed build constraint expressions.

When 'go get' builds packages, it still applies build constraints for
the target platform.

Fixes #32345

Change-Id: I6dceae6f10a5185870537de730b36292271ad124
Reviewed-on: https://go-review.googlesource.com/c/go/+/179898Reviewed-by: Bryan C. Mills <bcmills@google.com>

We need to make sure that there's no possible faulting
instruction between a VarDef and that variable being
fully initialized. If there was, then anything scanning
the stack during the handling of that fault will see
a live but uninitialized variable on the stack.

If we have:

  NilCheck p
  VarDef x
  x = *p

We can't rewrite that to

  VarDef x
  NilCheck p
  x = *p

Particularly, even though *p faults on p==nil, we still
have to do the explicit nil check before the VarDef.

Fixes #32288

Change-Id: Ib8b88e6a5af3bf6f238ff5491ac86f53f3cf9fc9
Reviewed-on: https://go-review.googlesource.com/c/go/+/179239
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>

Some runtime functions, like getcallerpc/sp, don't have Go or
assembly implementations and have to be intrinsified. Make sure
they are, even if intrinsics are disabled.

This makes "go build -gcflags=all=-d=ssa/intrinsics/off hello.go"
work.

Change-Id: I77caaed7715d3ca7ffef68a3cdc9357f095c6b9f
Reviewed-on: https://go-review.googlesource.com/c/go/+/179897
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Previously, we used the passed-in statVers as the basis for tag search,
but it is not always valid.
Instead, use info.Name, which (by precondition) must be valid.

Updates #32161
Updates #27171

Change-Id: Iaecb5043bdf2fefd26fbe3f8e3714b07d22f580f
Reviewed-on: https://go-review.googlesource.com/c/go/+/179857
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

The gccgo compiler crashes with int-to-string conversion with
large integer constant operand. CL 179777 is the fix. This CL
adds a test.

Updates #32347.

Change-Id: Id1d9dbbcdd3addca4636f1b9c5fdbc450cc48c1d
Reviewed-on: https://go-review.googlesource.com/c/go/+/179797
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Rework this recently introduced test case to insure that it works with
older versions of the OS. It was using a new framework library not
available on pre-10.14 to trigger the weak symbol reference; switch to
using a new symbol from an existing library. Tested on MacOS 10.14 and
10.11.

Updates #32233.

Change-Id: I1fe2a9255fca46cb7cdf33ff7fed67bba86fdc22
Reviewed-on: https://go-review.googlesource.com/c/go/+/179837
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

Fixes #32161
Updates #31251

Change-Id: I22760836b48cd734b90bc43aacb23e23e38c0f4e
Reviewed-on: https://go-review.googlesource.com/c/go/+/178497Reviewed-by: Bryan C. Mills <bcmills@google.com>

In addition to the example that was added in 203b80ab, mention these
special cases in the doc comment. This change also adjusts the example
to include "+Inf", as it was not otherwise mentioned that the plus
symbol may be present.

Fix #30990

Change-Id: I97d66f4aff6a17a6ccc0ee2e7f32e39ae91ae454
Reviewed-on: https://go-review.googlesource.com/c/go/+/179738Reviewed-by: Alex Miasoedov <msoedov@gmail.com>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #32328

Change-Id: Iee71ecb247f2c439804c2ff03a6ed7b7f5a8b562
Reviewed-on: https://go-review.googlesource.com/c/go/+/179603
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I0c7da31e94307f939e1a2f023e00d5b24bac0ea6
Reviewed-on: https://go-review.googlesource.com/c/go/+/179604
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #32325

Change-Id: Ic06938c36a25ef1a6623e35e128b73729d02d955
Reviewed-on: https://go-review.googlesource.com/c/go/+/179698
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

HTTP 408 responses now exist and are seen in the wild (e.g. from
Google's GFE), so make Go's HTTP client not spam about them when seen.
They're normal (now).

Fixes #32310

Change-Id: I558eb4654960c74cf20db1902ccaae13d03310f6
Reviewed-on: https://go-review.googlesource.com/c/go/+/179457
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

On unix if exec.Command() is given both ExtraFiles and Ctty, and the
Ctty file descriptor overlaps the range of FDs intended for the child,
then cmd.Start() the ioctl(fd,TIOCSCTTY) call fails with an
"inappropriate ioctl for device" error.

When child file descriptors overlap the new child's ctty the ctty will
be closed in the fd shuffle before the TIOCSCTTY.  Thus TIOCSCTTY is
used on one of the ExtraFiles rather than the intended Ctty file.  Thus
the error.

exec.Command() callers can workaround this by ensuring the Ctty fd is
larger than any ExtraFiles destined for the child.

Fix this by doing the ctty ioctl before the fd shuffle.

Test for this issue by modifying TestTerminalSignal to use more
ExtraFiles.  The test fails on linux and freebsd without this change's
syscall/*.go changes.  Other platforms (e.g. darwin, aix, solaris) have
the same fd shuffle logic, so the same fix is applied to them.  However,
I was only able to test on linux (32 and 64 bit) and freebsd (64 bit).

Manual runs of the test in https://golang.org/issue/29458 start passing
with this patch:
  Before:
    % /tmp/src/go/bin/go run t
    successfully ran child process with ParentExtraFileFdNum=5, ChildExtraFileFd=6, ParentPtyFd=7

    panic: failed to run child process with ParentExtraFileFdNum=10, ChildExtraFileFd=11, ParentPtyFd=11: fork/exec /bin/true: inappropriate ioctl for device

  After:
    % /tmp/src/go/bin/go run t
    successfully ran child process with ParentExtraFileFdNum=5, ChildExtraFileFd=6, ParentPtyFd=7

    successfully ran child process with ParentExtraFileFdNum=10, ChildExtraFileFd=11, ParentPtyFd=11

Fixes #29458
Change-Id: I99513de7b6073c7eb855f1eeb4d1f9dc0454ef8b
Reviewed-on: https://go-review.googlesource.com/c/go/+/178919
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Also: add a comment in internal/get.newUpgrader as a follow-up to
CL 177677.

Updates #26902

Change-Id: Ibce2807ecb44fa21697ca04a51c44ddca0f661d8
Reviewed-on: https://go-review.googlesource.com/c/go/+/176902Reviewed-by: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #32038

Change-Id: Ib4981f76572405363f404ee5038a45cb1752a2ad
Reviewed-on: https://go-review.googlesource.com/c/go/+/177879
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>

Test case for issue 32233.

Updates #32233.

Change-Id: I0e3b4a46832f39de4ef36d8fd8c6070bf9b1a019
Reviewed-on: https://go-review.googlesource.com/c/go/+/178726Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Checks if modules are enabled in GOPATH mode for go mod [graph, verify].
Added tests for GO111MODULE=[auto, off].

Fixes: #31237

Change-Id: I91efccfa10d0b2385ec2af1ea133deaa8234ba37
Reviewed-on: https://go-review.googlesource.com/c/go/+/174697
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Jay Conrod <jayconrod@google.com>