Chris Broadfoot [Mon, 7 Aug 2017 17:28:03 +0000 (10:28 -0700)]
[release-branch.go1.9] all: merge master into release-branch.go1.9
579120323f runtime: mapassign_* should use typedmemmove to update keys 380525598c all: remove some manual hyphenation f096b5b340 runtime: mark activeModules nosplit/nowritebarrier 3e3da54633 math/bits: fix example for OnesCount64 9b1e7cf2ac math/bits: add examples for OnesCount functions b01db023b1 misc/cgo/testsanitizers: also skip tsan11/tsan12 when using GCC a279b53a18 reflect: document how DeepEqual handles cycles 909f409a8d doc: mention handling of moved GOROOT in 1.9 release notes 58ad0176ca doc: use better wording to explain type-aware completion 92dac21d29 doc: replace paid with commercial 9bb98e02de doc/1.9: add CL 43712, ReverseProxy of HTTP/2 trailers to the release notes. 78d74fc2cd doc: clarify that Gogland is for paid IntelliJ platform IDEs 5495047223 doc/1.9: fix broken html link in CL 53030/53210 890e0e862f doc: fix bad link in go1.9 release notes be596f049a doc/1.9: fix stray html in CL 53030 0173631d53 encoding/binary: add examples for varint functions ac0ccf3cd2 doc/1.9: add CL 36696 for crypto/x509 to the release notes cc402c2c4d doc: hide blog content for golang.google.cn f396fa4285 internal/poll: don't add non-sockets to runtime poller 664cd26c89 cmd/vet: don't exit with failure on type checking error a8730cd93a doc: hide video and share if being served from CN b63db76c4a testsanitizers: check that tsan program runs, skip tsan10 on gcc 193eda7291 time: skip ZoneAbbr test in timezones with no abbreviation 6f08c935a9 cmd/go: show examples with empty output in go test -list f20944de78 cmd/compile: set/unset base register for better assembly print 623e2c4603 runtime: map bitmap and spans during heap initialization 780249eed4 runtime: fall back to small mmaps if we fail to grow reservation 31b2c4cc25 .github: add .md extension to SUPPORT file ac29f30dbb plugin: mention that there are known bugs with plugins 45a4609c0a cmd/dist: skip moved GOROOT on Go's Windows builders when not sharding tests e157fac02d test: add README 835dfef939 runtime/pprof: prevent a deadlock that SIGPROF might create on mips{,le} df91b8044d doc: list editor options by name, not plugin name 3d9475c04b doc: cleanup editor page b9661a14ea doc: add Atom to editor guide ee392ac10c cmd/compile: consider exported flag in namedata
Ian Lance Taylor [Fri, 4 Aug 2017 17:36:40 +0000 (10:36 -0700)]
runtime: mark activeModules nosplit/nowritebarrier
The activeModules function is called by the cgo pointer checking code,
which is called by the write barrier (when GODEBUG=cgocheck=2), and as
such must be nosplit/nowritebarrier.
doc: use better wording to explain type-aware completion
Some editors can filter the autocompletion suggestions based on
whether the code will compile once autocompleted. Explain this
feature with better wording.
Dmitry Savintsev [Fri, 4 Aug 2017 08:12:21 +0000 (10:12 +0200)]
doc/1.9: fix broken html link in CL 53030/53210
Change-Id: I7176becd10ad84cbfc3fb9427e190028626e5baf
Reviewed-on: https://go-review.googlesource.com/53291 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Alberto Donizetti [Fri, 4 Aug 2017 10:13:33 +0000 (12:13 +0200)]
doc: fix bad link in go1.9 release notes
Change-Id: I64ba37428f5cc560f0f20fe039feaecf5fcda93e
Reviewed-on: https://go-review.googlesource.com/53330 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Dmitry Savintsev [Thu, 3 Aug 2017 14:51:32 +0000 (16:51 +0200)]
doc/1.9: add CL 36696 for crypto/x509 to the release notes
add https://go-review.googlesource.com/c/36696
"crypto/x509: ignore CN if SAN extension present"
to the release notes.
Fixes #21289
Change-Id: Ifa184d3816806a8da3c67b68476c923329acf13e
Reviewed-on: https://go-review.googlesource.com/53030 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Andrew Bonventre [Thu, 3 Aug 2017 16:33:26 +0000 (12:33 -0400)]
doc: hide blog content for golang.google.cn
/blog redirects to blog.golang.org (currently blocked in China)
unless there is a local checkout of golang.org/x/blog, which is
not possible on App Engine Classic.
Change-Id: Ia695e663c9bebcc6c3bedea324c630299eaad4dc
Reviewed-on: https://go-review.googlesource.com/53051 Reviewed-by: Chris Broadfoot <cbro@golang.org>
Alberto Donizetti [Tue, 1 Aug 2017 15:41:51 +0000 (17:41 +0200)]
time: skip ZoneAbbr test in timezones with no abbreviation
The testZoneAbbr assumes that
Parse(RFC1123, t1.Format(RFC1123))
will always succeed. This is not true because Format will fall back to
the numeric zone (ex. -07) for timezones with no abbreviation, but
Parse won't accept the numeric zone when the layout specifies 'MST'
(an abbreviation).
Skip the zone abbreviation test in timezones with no abbreviation.
cmd/go: show examples with empty output in go test -list
Fixes #21205
Change-Id: I81b001eb42cbf2a5d5b7b82eb63548b22f501be5
Reviewed-on: https://go-review.googlesource.com/52110 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
cmd/compile: set/unset base register for better assembly print
For address of an auto or arg, on all non-x86 architectures
the assembler backend encodes the actual SP offset in the
instruction but leaves the offset in Prog unchanged. When the
assembly is printed in compile -S, it shows an offset
relative to pseudo FP/SP with an actual hardware SP base
register (e.g. R13 on ARM). This is confusing. Unset the
base register if it is indeed SP, so the assembly output is
consistent. If the base register isn't SP, it should be an
error and the error output contains the actual base register.
For address loading instructions, the base register isn't set
in the compiler on non-x86 architectures. Set it. Normally it
is SP and will be unset in the change mentioned above for
printing. If it is not, it will be an error and the error
output contains the actual base register.
No change in generated binary, only printed assembly. Passes
"go build -a -toolexec 'toolstash -cmp' std cmd" on all
architectures.
[release-branch.go1.9] runtime: map bitmap and spans during heap initialization
We lazily map the bitmap and spans areas as the heap grows. However,
right now we're very slightly too lazy. Specifically, the following
can happen on 32-bit:
1. mallocinit fails to allocate any heap arena, so
arena_used == arena_alloc == arena_end == bitmap.
2. There's less than 256MB between the end of the bitmap mapping and
the next mapping.
3. On the first allocation, mheap.sysAlloc sees that there's not
enough room in [arena_alloc, arena_end) because there's no room at
all. It gets a 256MB mapping from somewhere *lower* in the address
space than arena_used and sets arena_alloc and arena_end to this
hole.
4. Since the new arena_alloc is lower than arena_used, mheap.sysAlloc
doesn't bother to call mheap.setArenaUsed, so we still don't have a
bitmap mapping or a spans array mapping.
5. mheap.grow, which called mheap.sysAlloc, attempts to fill in the
spans array and crashes.
Fix this by mapping the metadata regions for the initial arena_used
when the heap is initialized, rather than trying to wait for an
allocation. This maintains the intended invariant that the structures
are always mapped for [arena_start, arena_used).
Fixes #21044.
Cherry-pick of CL 51714. Fixes #21234.
Change-Id: I4422375a6e234b9f979d22135fc63ae3395946b0
Reviewed-on: https://go-review.googlesource.com/52191
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
[release-branch.go1.9] runtime: fall back to small mmaps if we fail to grow reservation
Right now, if it's possible to grow the arena reservation but
mheap.sysAlloc fails to get 256MB more of memory, it simply fails.
However, on 32-bit we have a fallback path that uses much smaller
mmaps that could take in this situation, but fail to.
This commit fixes mheap.sysAlloc to use a common failure path in case
it can't grow the reservation. On 32-bit, this path includes the
fallback.
Ideally, mheap.sysAlloc would attempt smaller reservation growths
first, but taking the fallback path is a simple change for Go 1.9.
Updates #21044 (fixes one of two issues).
Cherry-pick of CL 51713. Updates #21234.
Change-Id: I1e0035ffba986c3551479d5742809e43da5e7c73
Reviewed-on: https://go-review.googlesource.com/52190
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
runtime: map bitmap and spans during heap initialization
We lazily map the bitmap and spans areas as the heap grows. However,
right now we're very slightly too lazy. Specifically, the following
can happen on 32-bit:
1. mallocinit fails to allocate any heap arena, so
arena_used == arena_alloc == arena_end == bitmap.
2. There's less than 256MB between the end of the bitmap mapping and
the next mapping.
3. On the first allocation, mheap.sysAlloc sees that there's not
enough room in [arena_alloc, arena_end) because there's no room at
all. It gets a 256MB mapping from somewhere *lower* in the address
space than arena_used and sets arena_alloc and arena_end to this
hole.
4. Since the new arena_alloc is lower than arena_used, mheap.sysAlloc
doesn't bother to call mheap.setArenaUsed, so we still don't have a
bitmap mapping or a spans array mapping.
5. mheap.grow, which called mheap.sysAlloc, attempts to fill in the
spans array and crashes.
Fix this by mapping the metadata regions for the initial arena_used
when the heap is initialized, rather than trying to wait for an
allocation. This maintains the intended invariant that the structures
are always mapped for [arena_start, arena_used).
Fixes #21044.
Change-Id: I4422375a6e234b9f979d22135fc63ae3395946b0
Reviewed-on: https://go-review.googlesource.com/51714
Run-TryBot: Austin Clements <austin@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
runtime: fall back to small mmaps if we fail to grow reservation
Right now, if it's possible to grow the arena reservation but
mheap.sysAlloc fails to get 256MB more of memory, it simply fails.
However, on 32-bit we have a fallback path that uses much smaller
mmaps that could take in this situation, but fail to.
This commit fixes mheap.sysAlloc to use a common failure path in case
it can't grow the reservation. On 32-bit, this path includes the
fallback.
Ideally, mheap.sysAlloc would attempt smaller reservation growths
first, but taking the fallback path is a simple change for Go 1.9.
Updates #21044 (fixes one of two issues).
Change-Id: I1e0035ffba986c3551479d5742809e43da5e7c73
Reviewed-on: https://go-review.googlesource.com/51713
Run-TryBot: Austin Clements <austin@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Gustav Westling [Sun, 30 Jul 2017 20:14:22 +0000 (22:14 +0200)]
.github: add .md extension to SUPPORT file
This makes GitHub render the markdown file automatically
on their web UI.
SUPPORT.md is the recommended file name according to the GitHub
documentation:
https://help.github.com/articles/adding-support-resources-to-your-project/
Vladimir Stefanovic [Thu, 4 May 2017 14:45:29 +0000 (16:45 +0200)]
runtime/pprof: prevent a deadlock that SIGPROF might create on mips{,le}
64bit atomics on mips/mipsle are implemented using spinlocks. If SIGPROF
is received while the program is in the critical section, it will try to
write the sample using the same spinlock, creating a deadloop.
Prevent it by creating a counter of SIGPROFs during atomic64 and
postpone writing the sample(s) until called from elsewhere, with
pc set to _LostSIGPROFDuringAtomic64.
Added a test case, per Cherry's suggestion. Works around #20146.
Ian Lance Taylor [Fri, 21 Jul 2017 23:37:40 +0000 (16:37 -0700)]
[release-branch.go1.9] cmd/compile: consider exported flag in namedata
It is possible to have an unexported name with a nil package,
for an embedded field whose type is a pointer to an unexported type.
We must encode that fact in the type..namedata symbol name,
to avoid incorrectly merging an unexported name with an exported name.
Fixes #21120
Change-Id: I2e3879d77fa15c05ad92e0bf8e55f74082db5111
Reviewed-on: https://go-review.googlesource.com/50710
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-on: https://go-review.googlesource.com/50970 Reviewed-by: Chris Broadfoot <cbro@golang.org>
Ian Lance Taylor [Fri, 21 Jul 2017 23:37:40 +0000 (16:37 -0700)]
cmd/compile: consider exported flag in namedata
It is possible to have an unexported name with a nil package,
for an embedded field whose type is a pointer to an unexported type.
We must encode that fact in the type..namedata symbol name,
to avoid incorrectly merging an unexported name with an exported name.
Fixes #21120
Change-Id: I2e3879d77fa15c05ad92e0bf8e55f74082db5111
Reviewed-on: https://go-review.googlesource.com/50710
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: David Crawshaw <crawshaw@golang.org>
Joe Tsai [Fri, 21 Jul 2017 23:53:54 +0000 (16:53 -0700)]
encoding/json: ignore embedded fields of pointers to unexported non-structs
https://golang.org/cl/33773 fixes the JSON marshaler to avoid serializing
embedded fields on unexported types of non-struct types. However, Go allows
embedding pointer to types, so the check for whether the field is a non-struct
type must first dereference the pointer to get at the underlying type.
Furthermore, due to a edge-case in the behavior of StructField.PkgPath not
being a reliable indicator of whether the field is unexported (see #21122),
we use our own logic to determine whether the field is exported or not.
The logic in this CL may be simplified depending on what happens in #21122.
Fixes #21121
Updates #21122
Change-Id: I8dfd1cdfac8a87950df294a566fb96dfd04fd749
Reviewed-on: https://go-review.googlesource.com/50711 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
From Josh's comments on https://golang.org/cl/50310
Once I removed the "from the Go standard library" bit, the beginning
wasn't worth keeping. It also wasn't clear whether what it meant by
"cache contention". Processor caches, or user-level caches built with
sync.Map? It didn't seem worth clarifying and didn't convey any useful
information, so deleted.
net/http: document that after Hijack, Request.Body is invalid
We can make it panic with a more explicit and readable error message
during Go 1.10, but document it for now. This has always been the
case; it's not a new rule.
Updates #20933
Change-Id: I53c1fefb47a8f4aae0bb32fa742afa3a2ed20e8a
Reviewed-on: https://go-review.googlesource.com/50634 Reviewed-by: Ian Lance Taylor <iant@golang.org> Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Dmitri Shuralyov [Wed, 19 Jul 2017 04:41:13 +0000 (00:41 -0400)]
net/http: improve signature of Redirect, NewRequest
In CL https://golang.org/cl/4893043 (6 years ago), a new package named
"url" was created (it is currently known as "net/url"). During that
change, some identifier name collisions were introduced, and two
parameters in net/http were renamed to "urlStr".
Since that time, Go has continued to put high emphasis on the quality
and readability of the documentation. Sometimes, that means making small
sacrifices in the implementation details of a package to ensure that
the godoc reads better, since that's what the majority of users interact
with. See https://golang.org/s/style#named-result-parameters:
> Clarity of docs is always more important than saving a line or two
> in your function.
I think the "urlStr" parameter name is suboptimal for godoc purposes,
and just "url" would be better.
During the review of https://golang.org/cl/4893043, it was also noted
by @rsc that having to rename parameters named "url" was suboptimal:
> It's unfortunate that naming the package url means
> you can't have a parameter or variable named url.
However, at the time, the name of the url package was still being
decided, and uri was an alternative name under consideration.
The reason urlStr was chosen is because it was a lesser evil
compared to naming the url package uri instead:
> Let's not get hung up on URI vs. URL, but I'd like s/uri/urlStr/ even for just
> that the "i" in "uri" looks very similar to the "l" in "url" in many fonts.
> Please let's go with urlStr instead of uri.
Now that we have the Go 1 compatibility guarantee, the name of the
net/url package is fixed. However, it's possible to improve the
signature of Redirect, NewRequest functions in net/http package
for godoc purposes by creating a package global alias to url.Parse,
and renaming urlStr parameter to url in the exported funcs. This CL
does so.
Bryan C. Mills [Tue, 9 May 2017 20:12:57 +0000 (16:12 -0400)]
sync: release m.mu during (*RWMutexMap).Range callbacks in sync_test
The mainline sync.Map has allowed mutations within Range callbacks
since https://golang.org/cl/37342. The reference implementations need
to do the same.
This change integrates https://go-review.googlesource.com/c/42956/
from x/sync.
cmd/go: fix test when go source tree has POSIX ACL
Fixes TestGoBuildUmask when the user has a POSIX ACL on the Go source tree.
Fixes #17909.
Change-Id: I5bc19099af8353afd41071258f4f317612b4c8c1
Reviewed-on: https://go-review.googlesource.com/50370 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
runtime: use SIGKILL if SIGQUIT is blocked; skip tests that need SIGQUIT
The runtime tests may be invoked from a parent that has SIGQUIT
blocked. For example, Java invokes subprocesses this way. In this
situation, TestCrashDumpsAllThreads and TestPanicSystemstack will fail
because they depend on SIGQUIT to get tracebacks, and any subprocess
test that times out will fail to kill the subprocess.
Fix this by detecting if SIGQUIT is blocked and, if so, skipping tests
that depend on it and using SIGKILL to kill timed-out subprocesses.
Based on a fix by Carl Henrik Lunde in
https://golang.org/issue/19196#issuecomment-316145733
Ian Lance Taylor [Thu, 20 Jul 2017 06:42:27 +0000 (23:42 -0700)]
runtime: don't call libc sigaction function in forked child
If we are using vfork, and if something (such as TSAN) is intercepting
the sigaction function, then we must call the system call, not the
libc function. Otherwise the intercepted sigaction call in the child
may trash the data structures in the parent.
The Go ecosystem provides many tools to make Go
development more productive and seamless. Document
the availability of the editor plugins and IDEs,
add an overview of feature support and screencasts.
Currently we trace mark assists even if they're satisfied entirely by
stealing. This means even if background marking is keeping up with
allocation, we'll still emit a trace event every N bytes of
allocation. The event will be a few microseconds, if that, but they're
frequent enough that, when zoomed out in the trace view, it looks like
all of the time is spent in mark assists even if almost none is.
Change this so we only emit a trace event if the assist actually has
to do assisting. This makes the traces of these events far more
useful.
Michael Munday [Mon, 17 Jul 2017 11:07:28 +0000 (07:07 -0400)]
cmd/compile: fix unaligned loads/stores to global variables on s390x
Load/store-merging and move optimizations can result in unaligned
memory accesses. This is fine so long as the load/store instruction
used does not take a relative offset. In the SSA rules this means we
must not merge (MOVDaddr (SB)) ops into loads/stores unless we can
guarantee the alignment of the target.
tSweepTerm and pauseStart are supposed to be when STW was triggered,
but right now they're captured a bit before STW. Move these down to
immediately before we trigger STW.
Currently, Windows stacks are either 128kB or 2MB depending on whether
the binary uses cgo. This is because we assume that Go system stacks
and the small amount of C code invoked by the standard library can
operate within smaller stacks, but general Windows C code assumes
larger stacks.
However, it's easy to call into arbitrary C code using the syscall
package on Windows without ever importing cgo into a binary. Such
binaries need larger system stacks even though they don't use cgo.
Fix this on 64-bit by increasing the system stack size to 2MB always.
This only costs address space, which is free enough on 64-bit to not
worry about. We keep (for now) the existing heuristic on 32-bit, where
address space comes at more of a premium.
Add Adam Kisala (individual CLA)
Add Aditya Mukerjee (individual CLA)
Add Akhil Indurti (individual CLA)
Add André Carvalho (individual CLA)
Add Andy Walker (individual CLA)
Add Awn Umar (individual CLA)
Add Bastian Ike (individual CLA)
Add Brian Downs (individual CLA)
Add Cody Oss (individual CLA)
Add Costin Chirvasuta (corporate CLA for Google Inc.)
Add Dan Ballard (individual CLA)
Add Dong-hee Na (individual CLA)
Add Dylan Waits (individual CLA)
Add Evan Hicks (individual CLA)
Add Fannie Zhang (corporate CLA for ARM Ltd.)
Add Francisco Rojas (individual CLA)
Add Gabriel Nicolas Avellaneda (individual CLA)
Add Gabríel Arthúr Pétursson (individual CLA)
Add Greg Poirier (individual CLA)
Add Iccha Sethi (individual CLA)
Add Ivan Moscoso (individual CLA)
Add Jamie Kerr (individual CLA)
Add Joe Kyo (individual CLA)
Add Joey Geiger (individual CLA)
Add John R. Lenton (individual CLA)
Add Johnny Luo (individual CLA)
Add Josh Roppo (individual CLA)
Add Kate Manson (individual CLA)
Add Leo Rudberg (corporate CLA for Google Inc.)
Add Ma Peiqi (individual CLA)
Add Martynas Budriūnas (corporate CLA for Google Inc.)
Add Maryan Hratson (individual CLA)
Add Michael Edwards (individual CLA)
Add Michael Hendricks (individual CLA)
Add Pablo Santiago Blum de Aguiar (individual CLA)
Add Pat Moroney (individual CLA)
Add Shi Han Ng (individual CLA)
Add Steven Buss (corporate CLA for Google Inc.)
Add Suzy Mueller (corporate CLA for Google Inc.)
Add Taro Aoki (individual CLA)
Add Tim Heckman (individual CLA)
Add Tony Walker (individual CLA)
Add Yasha Bubnov (individual CLA)
Updates #12042
Change-Id: Iee063dd6c5a39de16907acfb5af87e81a05ab417
Reviewed-on: https://go-review.googlesource.com/49351 Reviewed-by: Andrew Bonventre <andybons@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Change-Id: Ia3e351169a4ebe6db5e5f37b668f23dc8c992c78
Reviewed-on: https://go-review.googlesource.com/48877
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
encoding/json: fix indentation in Decode stream example
The existing example for Decoder.Decode (Stream) had excessive
indentation in the godoc interface for the const jsonStream,
making it hard to read. This fixes the indentation in the
example_test.go to improve the readability in godoc.
Ivan Moscoso [Sat, 15 Jul 2017 17:53:48 +0000 (11:53 -0600)]
regexp: clarify example for 'FindString'
Clarifying that FindString only provides left-most match
Change-Id: Ic6ecec12cca759fd4b3565ef5901a110843ffd56
Reviewed-on: https://go-review.googlesource.com/48609 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Pablo Santiago Blum de Aguiar [Sat, 15 Jul 2017 18:13:45 +0000 (12:13 -0600)]
strings: add example for IndexByte
Change-Id: Ib6a59735381ce744553f1ac96eeb65a194c8da10
Reviewed-on: https://go-review.googlesource.com/48860 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Change-Id: I69d1359d8868d4c5b173e4d831e38cea7dfeb713
Reviewed-on: https://go-review.googlesource.com/48859 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
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: If581bd4e9d9b4421e2ae20582c596fccb73d9aed
Reviewed-on: https://go-review.googlesource.com/48866 Reviewed-by: Ian Lance Taylor <iant@golang.org>