Glibc uses some special signals for special thread operations.  These
signals will be used in programs that use cgo and invoke certain glibc
functions, such as setgid.  In order for this to work, these signals
need to not be masked by any thread.  Before this change, they were
being masked by programs that used os/signal.Notify, because it
carefully masks all non-thread-specific signals in all threads so that a
dedicated thread will collect and report those signals (see ensureSigM
in signal1_unix.go).

This change adds the two glibc special signals to the set of signals
that are unmasked in each thread.

Fixes #12498.

Change-Id: I797d71a099a2169c186f024185d44a2e1972d4ad
Reviewed-on: https://go-review.googlesource.com/14297Reviewed-by: David Crawshaw <crawshaw@golang.org>

This puts the _Root* indexes in a more friendly order and tweaks
markrootSpans to use a for-range loop instead of its own indexing.

Change-Id: I2c18d55c9a673ea396b6424d51ef4997a1a74825
Reviewed-on: https://go-review.googlesource.com/14548Reviewed-by: Rick Hudson <rlh@golang.org>

Commit 0e6a6c51 removed readyExecute a long time ago, but left behind
the g.readyg field that was used by readyExecute. Remove this now
unused field.

Change-Id: I41b87ad2b427974d256ec7a7f6d4bdc2ce8a13bb
Reviewed-on: https://go-review.googlesource.com/13111Reviewed-by: Rick Hudson <rlh@golang.org>

This is a cleanup following cc8f5441, which was a minimal change to fix
issue #11617. This consolidates the two places in mSpan_Sweep that
update sweepgen. Previously this was necessary because sweepgen must
be updated before freeing the span, but we freed large spans early.
Now we free large spans later, so there's no need to duplicate the
sweepgen update. This also means large spans can take advantage of the
sweepgen sanity checking performed for other spans.

Change-Id: I23b79dbd9ec81d08575cd307cdc0fa6b20831768
Reviewed-on: https://go-review.googlesource.com/12451Reviewed-by: Rick Hudson <rlh@golang.org>

Marking of span roots can represent a significant fraction of the time
spent in mark termination. Simply traversing the span list takes about
1ms per GB of heap and if there are a large number of finalizers (for
example, for network connections), it may take much longer.

Improve the situation by splitting the span scan into 128 subtasks
that can be executed in parallel and load balanced by the markroots
parallel for. This lets the GC balance this job across the Ps.

A better solution is to do this during concurrent mark, or to improve
it algorithmically, but this is a simple change with a lot of bang for
the buck.

This was suggested by Rhys Hiltner.

Updates #11485.

Change-Id: I8b281adf0ba827064e154a1b6cc32d4d8031c03c
Reviewed-on: https://go-review.googlesource.com/13112Reviewed-by: Keith Randall <khr@golang.org>

The call to hash the trace stack reversed the "seed" and "size"
arguments to memhash and, hence, always called memhash with a 0 size,
which dutifully returned a hash value that depended only on the number
of PCs in the stack and not their values. As a result, all stacks were
put in to a very subset of the 8,192 buckets.

Fix this by passing these arguments in the correct order.

Change-Id: I67cd29312f5615c7ffa23e205008dd72c6b8af62
Reviewed-on: https://go-review.googlesource.com/13613Reviewed-by: Dmitry Vyukov <dvyukov@google.com>

Passes go build -a -toolexec 'toolstash -cmp' std cmd

Change-Id: Ief4613cfb341172a85e3a894f44fb2bb308c7b55
Reviewed-on: https://go-review.googlesource.com/14554
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>

Fixes #12606

Change-Id: Ib68cb20108ad35c3dd96e606649c4c8f9c0f085c
Reviewed-on: https://go-review.googlesource.com/14571Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: Id07811a25bf4aa3ff834e7254a3dfb04522b2926
Reviewed-on: https://go-review.googlesource.com/14174Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>

Fixes #11959

This test runs 100 concurrent callbacks from C to Go consuming 100
operating system threads, which at 8mb a piece (the default on linux/arm)
would reserve over 800mb of address space. This would frequently
cause the test to fail on platforms with ~1gb of ram, such as the
raspberry pi.

This change reduces the thread stack allocation to 256kb, a number picked
at random, but at 1/32th the previous size, should allow the test to
pass successfully on all platforms.

Change-Id: I8b8bbab30ea7b2972b3269a6ff91e6fe5bc717af
Reviewed-on: https://go-review.googlesource.com/13731
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Capitanio <capnm9@gmail.com>
Reviewed-by: Minux Ma <minux@golang.org>

It's because runtime links to ntdll, and ntdll exports a couple
incompatible libc functions. We must link to msvcrt first and
then try ntdll.

Fixes #12030.

Change-Id: I0105417bada108da55f5ae4482c2423ac7a92957
Reviewed-on: https://go-review.googlesource.com/14472Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Although bnum was being called with a Bits value, a limitation
of the escape analyser (golang/go#12588) meant that taking the
address of the Bits.b array in the range statement caused the
formal parameter to escape to the heap.

Passing the a pointer to a Bits, as with all the other Bits helper
methods avoids the allocation.

Before:
BenchmarkBnum1-4        20000000                69.6 ns/op            32 B/op          1 allocs/op

After:
BenchmarkBnum1-4        100000000               10.1 ns/op             0 B/op          0 allocs/op

Change-Id: I673bd57ddc032ee67d09474156d795fb1ba72018
Reviewed-on: https://go-review.googlesource.com/14501Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #12578.

Change-Id: I257d70a67609463e24936bc1739285da154be2fe
Reviewed-on: https://go-review.googlesource.com/14531Reviewed-by: Rob Pike <r@golang.org>

The current version of go/printer formats the following code
like this:

	foo.Bar().
		Run(func() {
		do()
	}).
		Set(map[string]interface{}{
		"x": "three",
		"y": 4,
	}).
		Run(
		func() {
			do()
		},
	)

This CL changes the go/printer behaviour to make the code look
like this.

	foo.Bar().
		Run(func() {
			do()
		}).
		Set(map[string]interface{}{
			"x": "three",
			"y": 4,
		}).
		Run(
			func() {
				do()
			},
		)

Fixes #12066.

Change-Id: If0f525dae1a5d45f9ba40534dbb65715d7e8001b
Reviewed-on: https://go-review.googlesource.com/13928Reviewed-by: Robert Griesemer <gri@golang.org>

Fixes #11626.

Change-Id: I1b70c0844473c3b57a53d7cca747ea5cdc68d232
Reviewed-on: https://go-review.googlesource.com/14526
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Simplify slice/map literal expressions.
Caught with gofmt -d -s, fixed with gofmt -w -s

Change-Id: I639cfb02b1f57dea4087863df3995889c9371529
Reviewed-on: https://go-review.googlesource.com/13837Reviewed-by: Andrew Gerrand <adg@golang.org>

Simplify slice/map literal expression.
Caught with gofmt -d -s

Change-Id: I7f38ef9fb528e2fd284bd0f190fbdf4a91956e55
Reviewed-on: https://go-review.googlesource.com/13834Reviewed-by: Andrew Gerrand <adg@golang.org>

Simplify slice/map literal expression.
Caught with gofmt -d -s, fixed with gofmt -w -s

Change-Id: I4472c6003cf66e65f6e69050872ff95c96f01253
Reviewed-on: https://go-review.googlesource.com/13836Reviewed-by: Andrew Gerrand <adg@golang.org>

Simplify slice/map literal expressions.
Caught with gofmt -d -s, fixed with gofmt -w -s
Checked that the result can still be compiled with Go 1.4.

Change-Id: I06bce110bb5f46ee2f45113681294475aa6968bc
Reviewed-on: https://go-review.googlesource.com/13839Reviewed-by: Andrew Gerrand <adg@golang.org>

Simplify slice/map literal expressions.
Caught with gofmt -d -s, fixed with gofmt -w -s
Checked that the result can still be compiled with Go 1.4.

Change-Id: I201cd90fdfb8de2971c46ad7fce64111152b697e
Reviewed-on: https://go-review.googlesource.com/13832Reviewed-by: Andrew Gerrand <adg@golang.org>

One (12466) was an actual logic error, backing up when there was
nothing there. The others were due to continuing to process an
instruction when it cannot work.

Methodically stop assembling an instruction when it's not going to
succeed.

Fixes #12466.
Fixes #12467.
Fixes #12468.

Change-Id: I88c568f2b9c1a8408043b2ac5a78f5e2ffd62abd
Reviewed-on: https://go-review.googlesource.com/14498Reviewed-by: Andrew Gerrand <adg@golang.org>

If comment of the archive contains data which looks like
a zip64 directory, the comment is parsed as an
actual directory header.
Commit adds some additional checks similar to the checks
in minizip library.

Fixes #12449

Change-Id: Ia0fc950e47b9c39f77d88401b9ca30100ca7c808
Reviewed-on: https://go-review.googlesource.com/14433
Run-TryBot: Andrew Gerrand <adg@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>

cmd/dist will re-exec itself to detect VFP support at run-time.

Fixes #9732, #12548.

Change-Id: I9ad0c5c7fa3e97bd79a32da372e1a962565bb3af
Reviewed-on: https://go-review.googlesource.com/3973Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I3d37391af2089881a5bd4d8f3e5d434b279c272e
Reviewed-on: https://go-review.googlesource.com/14490Reviewed-by: Chris Manghane <cmang@golang.org>

It was correct for an early version of the CL which introduced the
type, but later versions of the CL changed the behavior without
updating the documentation.

Fixes #12568

Change-Id: Ia4090a02ba122e9f8317ed86c4c9839ae2c539e0
Reviewed-on: https://go-review.googlesource.com/14496Reviewed-by: Ian Lance Taylor <iant@golang.org>

Simplify slice/map literal expressions.
Caught with gofmt -d -s, fixed with gofmt -w -s
Checked that the result can still be compiled with Go 1.4.

Change-Id: I0a6773d12200a7b43491f25f914335069a1fa5e8
Reviewed-on: https://go-review.googlesource.com/13833Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #12531.

Change-Id: I66dc7ac1b71b8f72b4a8f3ec18befa2607ef358b
Reviewed-on: https://go-review.googlesource.com/14494Reviewed-by: Rob Pike <r@golang.org>

Change-Id: Ie86b703407f0f655a4552dd6e03df5f263be43db
Reviewed-on: https://go-review.googlesource.com/14492Reviewed-by: Rob Pike <r@golang.org>

The construction
	fmt.Printf("%*d", n, 4)
reads the argument n as a width specifier to use when printing 4.
Until now, only strict int type was accepted here and it couldn't
be fixed because the fix, using reflection, broke escape analysis
and added an extra allocation in every Printf call, even those that
do not use this feature.

The compiler has been fixed, although I am not sure when exactly,
so let's fix Printf and then write

Fixes #10732.

Change-Id: I79cf0c4fadd876265aa39d3cb62867247b36ab65
Reviewed-on: https://go-review.googlesource.com/14491Reviewed-by: Ian Lance Taylor <iant@golang.org>

In Parse, one can now say Feb 31 or even Feb 99. This is easy
to explain, consistent with time.Date, and even maybe useful.

Fixes #12333.
Fixes #7268. (By disagreeing with it.)

Change-Id: I7b95c842528bed66933681c8b9cc00640fccfcb4
Reviewed-on: https://go-review.googlesource.com/14123Reviewed-by: Ian Lance Taylor <iant@golang.org>

Updates #11241

Change-Id: I0614c5a9a7a4c399ad5d664f36c70c3210911905
Reviewed-on: https://go-review.googlesource.com/14356Reviewed-by: Robert Griesemer <gri@golang.org>

this leaves lots of cruft behind, will delete that soon

Change-Id: I12d6b6192f89bcdd89b2b0873774bd3458373b8a
Reviewed-on: https://go-review.googlesource.com/14196Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Disassembler for mips64 is not supported yet.

Change-Id: Ie923dd1e37fed47fc395b9d1cd9194e55020bee5
Reviewed-on: https://go-review.googlesource.com/14459Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Because external linking is not supported for now.

Change-Id: Icdd8f3cb3bfb781a990e529fce9129d91e98a9ec
Reviewed-on: https://go-review.googlesource.com/14457Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

It went out of its way to look for implicit assignments
but never checked explicit assignments.

This detects the root bug for #12099.

Change-Id: I6a6e774cc38749ea8be7cfd58ba6421247b67000
Reviewed-on: https://go-review.googlesource.com/13646Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Rob Pike <r@golang.org>

CL 14315 broke the tests for parsing loosely formed remote package
metadata. Switch the parsing to use RawToken to recover the previous
behaviour that Token provided.

It could be argued that the parser should be stricter, but as remote
metadata has been readable with the parser for several years, it is
safer to change the parser to continue to accept the samples provided
in the test cases.

Change-Id: I2a3ba1757d3cff53b1a1c4386276955bb46cf8cd
Reviewed-on: https://go-review.googlesource.com/14482Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This one of a set of changes to make the transition away from NodeList
easier by removing cases in which NodeList doesn't act semi-trivially like a
[]*Node.

This CL was originally prepared by Josh Bleecher Snyder <josharian@gmail.com>.

This change passes go build -toolexec 'toolstash -cmp' -a std.

Change-Id: Ie02d2cf35f1e8438c6e9dc1d5fba51e8adde1bc0
Reviewed-on: https://go-review.googlesource.com/14480Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Update #12563.

Change-Id: Id87f8e53586accd662575c31961c39787268df7a
Reviewed-on: https://go-review.googlesource.com/14471
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #12350.

Change-Id: I3dcb0e2190c11f83f15fb07cc637fead54f734f7
Reviewed-on: https://go-review.googlesource.com/14275Reviewed-by: Ian Lance Taylor <iant@golang.org>

Currently, the xml.Decoder's Token routine returns successfully for
XML input that does not properly close root start elements (and any
unclosed descendants). For example, all the following inputs

    <root>
    <root><foo>
    <root><foo></foo>

cause Token to return with nil and io.EOF, indicating a successful
parse.

This change fixes that. It leaves the semantics of RawToken intact.

Fixes #11405

Change-Id: I6f1328c410cf41e17de0a93cf357a69f12c2a9f7
Reviewed-on: https://go-review.googlesource.com/14315Reviewed-by: Nigel Tao <nigeltao@golang.org>