While there's an example for SectionReader.Seek, if someone is
seeking documentation specifically about Seeker.Seek, they may
not immediately find the SectionReader example. Offset and whence
may not be entirely intuitive to new developers either, so include
examples of both positive/negative offsets and SeekStart/SeekEnd.

Change-Id: I5b7442ccf683d9706e9261c11bc0ea31a1ac21d4
Reviewed-on: https://go-review.googlesource.com/48873Reviewed-by: Kevin Burke <kev@inburke.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: If581bd4e9d9b4421e2ae20582c596fccb73d9aed
Reviewed-on: https://go-review.googlesource.com/48866Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: I994f003c97a14d194df5f07dd217c0ff3b214741
Reviewed-on: https://go-review.googlesource.com/48874Reviewed-by: Matt Layher <mdlayher@gmail.com>
Run-TryBot: Matt Layher <mdlayher@gmail.com>

The existing example for FileMode using Stat to get FileInfo.
But, Stat cannot get symlink info, it need to use Fstat instead.

Change-Id: I5cc38cd10caaa5912946abe2a2b90995a91ee10f
Reviewed-on: https://go-review.googlesource.com/47370Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>

Fails on iOS because CC_FOR_TARGET points to clangwrap.sh in the
original GOROOT. We could fix that but it doesn't seem worth it.

Fails on Android with "exec format error". I'm not sure why but I
doubt it is interesting.

Fails on Plan 9 because the original GOROOT is being preserved in some
unknown way. This is issue #21016.

Updates #21016

Change-Id: I4e7115d734fc7bf21e5a2ba18fb6ad0bfa31c735
Reviewed-on: https://go-review.googlesource.com/48650
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: David du Colombier <0intro@gmail.com>
Reviewed-by: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

I just want to experience the whole Gerrit Flow, so I make this simple commit
as my first commit to golang src repo.

Change-Id: Ie744573beac7a8b9361f898fac269c9d88010493
Reviewed-on: https://go-review.googlesource.com/48630Reviewed-by: Ma Peiqi <mapeiqi2017@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

When StructOf is used with an anonymous field that has methods, and
that anonymous field is not the first field, the methods we generate
are incorrect because they do not offset to the field as required.
If we encounter that case, panic rather than doing the wrong thing.

Fixes #20824
Updates #15924

Change-Id: I3b0901ddbc6d58af5f7e84660b5e3085a431035d
Reviewed-on: https://go-review.googlesource.com/47035
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates #18997

Change-Id: Ib1961a4c26b42f99b98b255beb7e2a74b632e0c1
Reviewed-on: https://go-review.googlesource.com/48551Reviewed-by: Joe Shaw <joe@joeshaw.org>
Reviewed-by: Tom Bergan <tombergan@google.com>

Neither the Gerrit UI nor its docs use the term CL or changelist.

Change-Id: Ic19fddc660ec4f008f10fd207e4ac6349431ff5d
Reviewed-on: https://go-review.googlesource.com/48595Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #17206

Change-Id: Id0ebc3a55ea1c5f52608decffee04c8398a8774b
Reviewed-on: https://go-review.googlesource.com/48571
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

This is necessary to make a relocated GOROOT work correctly.

Fixes #20997

Change-Id: I18624bd2e109721066cd9e4a887a12583ab79f5d
Reviewed-on: https://go-review.googlesource.com/48550
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The current implementation ignores certificates that exist
in the login and System keychains.

This change adds the missing System and login keychain
files to the `/usr/bin/security` command in
`execSecurityRoots`. If the current user cannot be
obtained, the login keychain is ignored.

Refs #16532

Change-Id: I8594a6b8940c58df8a8015b274fa45c39e18862c
Reviewed-on: https://go-review.googlesource.com/36941
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The escaper contains information about which templates have already been
visited and escaped. This information is necessary to prevent templates
that have already been escaped from being over-escaped. However, since we
currently create a new escaper each time we execute a template, this
information does not persist across multiple template executions.

Fix this by saving an escaper in each template name space which is shared by
all templates in that name space.

While there, fix error message formatting for an escaping unit test.

Fixes #20842

Change-Id: Ie392c3e7ce0e0a9947bdf56c99e926e7c7db76e4
Reviewed-on: https://go-review.googlesource.com/47256Reviewed-by: Mike Samuel <mikesamuel@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Previous code failed to account for particular control flow
involving nested loops when updating phi function inputs.
Fix involves:
1) remove incorrect shortcut
2) generate a "better" order for children in dominator tree
3) note inner-loop updates and check before applying
   outer-loop updates.

Fixes #20675.

Change-Id: I2fe21470604b5c259e777ad8b15de95f7706894d
Reviewed-on: https://go-review.googlesource.com/45791
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

If we get an EAGAIN error on an unpollable file, don't try to wait for
it to be ready; just return EAGAIN.

It's possible that we should instead ensure that when Stdin is a pipe
in non-blocking mode, we wait for data to appear. For now take the
conservative approach of doing what we did in previous releases.

Based on https://golang.org/cl/47555 by Totoro W.

Fixes #20915

Change-Id: Icc9e97a5a877b0a3583ec056c35412d1afab62d1
Reviewed-on: https://go-review.googlesource.com/48490
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I73fdc793bbc3ffe9ace1bfa78799f84c31630d61
Reviewed-on: https://go-review.googlesource.com/48391Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: If9f64fbb78009921e8773124e4e5eb8a871095a5
Reviewed-on: https://go-review.googlesource.com/48192Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>

CL 44352 changed the behavior of SIGINT, which can break tests that
themselves use SIGINT.  I think we can only implement this if the
testing package has a way to know whether the code under test is using
SIGINT, but os/signal does not provide an API for that.  Roll back for
1.9 and think about this again for 1.10.

Updates #19397

Change-Id: I021c314db2b9d0a80d0088b120a6ade685459990
Reviewed-on: https://go-review.googlesource.com/48370
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

It seems that when too much other code is running on the system,
the testprogcgo code can overrun its timeouts.

Updates #18598.

Not marking the issue as fixed until it doesn't recur for some time.

Change-Id: Ieaf106b41986fdda76b1d027bb9d5e3fb805cc3b
Reviewed-on: https://go-review.googlesource.com/48233
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Usually this test is skipped (on builders and when not root), so
people are unlikely to see this error.

Updates #19296

Change-Id: I3acb81260034dad8776c305f83d7cbac4b718e75
Reviewed-on: https://go-review.googlesource.com/48191
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #20948

Change-Id: I222bf101a5c1bdc5cbb0970949070c4b58b9b83b
Reviewed-on: https://go-review.googlesource.com/48190Reviewed-by: Ian Lance Taylor <iant@golang.org>

SysV semaphore undo lists should be shared by threads, just like
several other resources listed in cloneFlags. Currently we don't do
this, but it probably doesn't affect anything because 1) probably
nobody uses SysV semaphores from Go and 2) Go-created threads never
exit until the process does. Beyond being the right thing to do,
user-level QEMU requires this flag because it depends on glibc to
create new threads and glibc uses this flag.

Fixes #20763.

Change-Id: I1d1dafec53ed87e0f4d4d432b945e8e68bb72dcd
Reviewed-on: https://go-review.googlesource.com/48170
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

To-be-released NetBSD 7.1.1 reportedly fixes the kernel panic that was
affecting our builders and is being released because of Go's warning.

So, soften our warning.

7.1.1 might work, but I can't get a builder up and running to verify
yet as it appears that Anita either doesn't support it yet, or the
NetBSD CDN doesn't have the files yet.

Change-Id: Ifaafc566879a6afdf1174e545ad10e240da427e8
Reviewed-on: https://go-review.googlesource.com/47970Reviewed-by: Ian Lance Taylor <iant@golang.org>

TestStackGrowth is currently a parallel test. However, it depends on a
20 second timeout, which is already dubious in a parallel test, and
became really problematic on slow builders when runtime.GC switched to
triggering concurrent GC instead of STW GC. Before that change, the
test spent much of its time in STW GC, so it wasn't *really* parallel.
After that change, it was competing with all of the other parallel
tests and GC likely started taking ~4 times longer. On most builders
the whole test runs in well under a second, but on the slow builders
that was enough to push it over the 20 second timeout.

Fix this by making the test serial.

Updates #19381 (probably fixes it, but we'll have to wait and see).

Change-Id: I21af7cf543ab07f1ec1c930bfcb355b0df75672d
Reviewed-on: https://go-review.googlesource.com/48110
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Elias Naur <elias.naur@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Local variables can also be relied on the be 64-bit aligned, since
they will be escaped to the heap if used with any atomic operations.

Also, allocated arrays are also aligned, just like structs and slices.

Fixes #18955.

Change-Id: I8a1897f6ff78922c8bfcf20d6eb4bcb17a70ba2d
Reviewed-on: https://go-review.googlesource.com/48112Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The current description refers to the outermost "frame" which can be
misleading. A user reading it can think it means a stack frame.

Change-Id: Ie2c7cb4b4db8f41572df206478ce3b46a0245a5d
Reviewed-on: https://go-review.googlesource.com/47850Reviewed-by: Austin Clements <austin@google.com>

When a local variable is moved to the heap the declaration position
should be preserved so that later on we can assign it to the correct
DW_TAG_lexical_block.

Fixes #20959

Change-Id: I3700ef53c68ccd506d0633f11374ad88a52b2898
Reviewed-on: https://go-review.googlesource.com/47852
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

ld.addpltsym adds an R_X86_64_JMP_SLOT dynamic relocation to .rela.plt
and uses Addaddrplus to reference the GOT in Elf64_Rela.r_offset.

Addaddrplus results in an R_ADDR relocation, which here we transform
into an R_X86_64_64 dynamic relocation. This is wrong for several
reasons:

1. .rela.plt is not a writable, relro section. It is mapped read-only,
   causing the dynamic linker to segfault when it tried to handle the
   relocation. This was the immediate cause of internal PIE cgo
   crashes.

2. Relocations targetting other reloc sections are, as far as I can
   tell, undefined behavior in the ELF spec and are unlikely to be a
   good idea.

3. Even if the relocation did work, it isn't what we want. The
   relocation, if successfully handled, would have put an absolute
   address as the JMP_SLOT offset, but it should be the offset from the
   beginning of the binary, just like any other relocation. What we want
   is a statically resolved R_ADDR relocation, just as is used below for
   the R_X86_64_64 relocation.

Skipping the .rela.plt allows reloc() to handle these R_ADDR
relocations.

With this CL, internal PIE cgo binaries work.

Updates #18968

Change-Id: Ie74e6fe249e88150baa0e340b1cb128cf7f28673
Reviewed-on: https://go-review.googlesource.com/47837Reviewed-by: Ian Lance Taylor <iant@golang.org>

On a slow or distracted machine, 0.1s is sometimes
not long enough for a non-blocking function call to complete.
This causes rare test flakes.
They can be easily reproduced by reducing the wait time to (say) 100ns.

For non-blocking functions, increase the window from 100ms to 10s.
Using different windows for block and non-blocking functions,
allows us to reduce the time for blocking functions.
The risk here is false negatives, but that risk is low;
this test is run repeatedly on many fast machines,
for which 10ms is ample time.
This reduces the time required to run the test by a factor of 10,
from ~1s to ~100ms.

Fixes #20299

Change-Id: Ice9a641a66c6c101d738a2ebe1bcb144ae3c9916
Reviewed-on: https://go-review.googlesource.com/47812
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Currently, sysmon waits 60 ms during idle before relaxing. This is
primarily to avoid reducing the precision of short-duration timers. Of
course, if there are no short-duration timers, this wastes 60 ms
running the timer at high resolution.

Improve this by instead inspecting the time until the next timer fires
and relaxing the timer resolution immediately if the next timer won't
fire for a while.

Updates #20937.

Change-Id: If4ad0a565b65a9b3e8c4cdc2eff1486968c79f24
Reviewed-on: https://go-review.googlesource.com/47833
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Currently, sysmon relaxes the Windows timer resolution as soon as the
Go process becomes idle. However, if it's going idle because of a
short sleep (< 15.6 ms), this can turn that short sleep into a long
sleep (15.6 ms).

To address this, wait for 60 ms of idleness before relaxing the timer
resolution. It would be better to check the time until the next wakeup
and relax immediately if it makes sense, but there's currently no
interaction between sysmon and the timer subsystem, so adding this
simple delay is a much simpler and safer change for late in the
release cycle.

Fixes #20937.

Change-Id: I817db24c3bdfa06dba04b7bc197cfd554363c379
Reviewed-on: https://go-review.googlesource.com/47832
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This reverts commit 168eb9cf.

CL 47831 fixes the issue with plugins on ARMv5, so we can re-enable the test.

Updates #19674.

Change-Id: Idcb29f93ffb0460413f1fab5bb82fa2605795038
Reviewed-on: https://go-review.googlesource.com/47834Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

R11 is callee-save in the C ABI, but the temporary register in the Go
ABI. Currently it's being clobbered by runtime.addmoduledata, which
has to follow the C ABI. The observed effect of this was that
dl_open_worker was returning to a bad PC because after it failed to
restore its SP because it was using R11 as a frame pointer.

Fix this by saving R11 around addmoduledata.

Fixes #19674.

Change-Id: Iaacbcc76809a3aa536e9897770831dcbcb6c8245
Reviewed-on: https://go-review.googlesource.com/47831
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

Change-Id: If1c602176e0bea66924983eab8edd5e450228b68
Reviewed-on: https://go-review.googlesource.com/47792Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

A lot of code that uses runtime.Callers makes assumptions about the
result that are not true today under gccgo and will not be true in the
future in gc. This adds a section to the release notes discussing how
to correctly use runtime.Callers.

Change-Id: I96b7c7ef183cee2061442fc3501fceceefa54c09
Reviewed-on: https://go-review.googlesource.com/47691Reviewed-by: Russ Cox <rsc@golang.org>

Change-Id: I1c02aa4f7131ae984fda66b32e8a993c0a40b8f4
Reviewed-on: https://go-review.googlesource.com/47690Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

Fixes #20930

Change-Id: I4a59de0556cffeae9af2eaa41609601e086211b2
Reviewed-on: https://go-review.googlesource.com/47731Reviewed-by: Rob Pike <r@golang.org>

Fixes #20928

Change-Id: I7f7aafb8ff4b5deb50c286a9ae81c34ee85e56a9
Reviewed-on: https://go-review.googlesource.com/47730Reviewed-by: Rob Pike <r@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

CL 47341 added support for decoding non-padded messages. But DecodedLen
still returned a multiple of 5 for messages without a padding, even
though it is possible to calculate the len exactly when using NoPadding.

This change makes DecodedLen return the exact number of bytes that
will be written. A change to the decoding logic is also made so that it
can handle this case.

DecodedLen now has the same behaviour as DecodedLen in encoding/base64.

Fixes #20854

Change-Id: I729e0b1c0946c866fb675c854f835f366dd4b5a4
Reviewed-on: https://go-review.googlesource.com/47710Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

It already implied that Cmd.Wait is more than os.Process.Wait, but say
so explicitly.

See https://github.com/golang/go/issues/18874#issuecomment-309921486

Updates #18874

Change-Id: Iaa46defd776ae0be817d9f4466a99ac78cfd672b
Reviewed-on: https://go-review.googlesource.com/47650Reviewed-by: Russ Cox <rsc@golang.org>