Jay Conrod [Fri, 4 Jan 2019 22:30:36 +0000 (17:30 -0500)]
cmd/go: deflake TestScript/gcflags_patterns
The check below can fail incorrectly if the buildid ends with '-p'.
! stderr 'compile.* -e .*-p [^z]'
This fix changes regular expressions to '-e.* -p' or '-N.* -p' instead
of '-e .*-p'. '-l' is no longer used because the compiler accepts
multiple flags starting with '-l' ('-e' and '-N' do not have this
problem), so there could be false matches.
Mainly to pull in the bug fix in the structtag pass, where filenames
could sometimes be wrong. The bug wasn't present in 1.11, so it was a
regression and needs fixing before 1.12 is out.
Fixes #29130.
Change-Id: Ie9d9bff84873f34d748ebd8f056b6bc2ac822a55
Reviewed-on: https://go-review.googlesource.com/c/156378
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Alan Donovan <adonovan@google.com>
Filippo Valsorda [Sat, 5 Jan 2019 00:27:08 +0000 (19:27 -0500)]
crypto/x509: ignore harmless edge case in TestSystemRoots
The no-cgo validation hack lets in certificates from the root store that
are not marked as roots themselves, but are signed by a root; the cgo
path correctly excludes them. When TestSystemRoots compares cgo and
no-cgo results it tries to ignore them by ignoring certificates which
pass validation, but expired certificates were failing validation.
Letting through expired certs is harmless anyway because we will refuse
to build chains to them.
Filippo Valsorda [Sat, 5 Jan 2019 00:09:01 +0000 (19:09 -0500)]
crypto/x509: ignore 5 phantom 1024-bit roots in TestSystemRoots
On macOS 10.11, but not 10.10 and 10.12, the C API returns 5 old root
CAs which are not in SystemRootCertificates.keychain (but seem to be in
X509Anchors and maybe SystemCACertificates.keychain, along with many
others that the C API does not return). They all are moribund 1024-bit
roots which are now gone from the Apple store.
Since we can't seem to find a way to make the no-cgo code see them,
ignore them rather than skipping the test.
David Chase [Fri, 4 Jan 2019 16:43:23 +0000 (11:43 -0500)]
cmd/compile: modify swt.go to skip repeated walks of switch
The compiler appears to contain several squirrelly corner
cases where nodes are double walked, some where new nodes
are created from walked parts. Rather than trust that we
had searched hard enough for the last one, change
exprSwitch.walk() to return immediately if it has already
been walked. This appears to be the only case where
double-walking a node is actually harmful.
Fixes #29562.
Change-Id: I0667e8769aba4c3236666cd836a934e256c0bfc5
Reviewed-on: https://go-review.googlesource.com/c/156317
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
Dmitri Shuralyov [Fri, 4 Jan 2019 00:44:55 +0000 (19:44 -0500)]
CONTRIBUTORS: first round of automated updates for Go 1.12
These updates have been automatically generated using a modified
version of the updateac command with the following changes:
- code to automatically update the AUTHORS file has been removed,
since we're not updating that file automatically after Go 1.11
(see CL 128877)
- CLA checking code has been removed, since it was primarily needed
for updating the AUTHORS file
- instead of executing the misc/sortac binary, its code was embedded
into the updateac command itself
The modified updateac command will be added to x/build repository soon,
and the misc/sortac command can be removed afterwards.
Austin Clements [Thu, 3 Jan 2019 19:48:30 +0000 (14:48 -0500)]
runtime: work around "P has cached GC work" failures
We still don't understand what's causing there to be remaining GC work
when we enter mark termination, but in order to move forward on this
issue, this CL implements a work-around for the problem.
If debugCachedWork is false, this CL does a second check for remaining
GC work as soon as it stops the world for mark termination. If it
finds any work, it starts the world again and re-enters concurrent
mark. This will increase STW time by a small amount proportional to
GOMAXPROCS, but fixes a serious correctness issue.
This works-around #27993.
Change-Id: Ia23b85dd6c792ee8d623428bd1a3115631e387b8
Reviewed-on: https://go-review.googlesource.com/c/156140
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Michael Knyszek <mknyszek@google.com> Reviewed-by: Rick Hudson <rlh@golang.org>
Jay Conrod [Thu, 3 Jan 2019 23:33:36 +0000 (18:33 -0500)]
cmd/go: fix failure in TestScript/build_runtime_gcflags
This test case failed on the longtest builder. It relied on
runtime/internal/atomic not being compiled with the -l flag in the
cache. The test case now creates its own GOCACHE, similar to
build_cache_compile and a few others.
Also, mention the correct issue the test case verifies.
Fixes #29395
Change-Id: Id50e9dfc50db03fb11582d3dd6b69c3e1ed750eb
Reviewed-on: https://go-review.googlesource.com/c/156237
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Fixes bug introduced by https://golang.org/cl/129059 where
gcflags='all=...' and ldflags='all=...' would not be applied to some
packages built by 'go test'.
LoadImport used to set gcflags/ldflags for the Package objects it
created, in https://golang.org/cl/129059 this code was factored out to
setToolFlags. The codepath of `go build` was updated to call
setToolFlags appropriatley, but the codepath of `go test -c` wasn't,
resulting in gcflags/ldflags being applied inconsistently when building
tests.
This commit changes TestPackagesFor to call setToolFlags on the package
objects it creates.
Fixes #27681
Change-Id: Idcbec0c989ee96ec066207184611f08818873e8d
Reviewed-on: https://go-review.googlesource.com/c/136275
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Jay Conrod <jayconrod@google.com>
Keith Randall [Mon, 31 Dec 2018 23:03:33 +0000 (15:03 -0800)]
cmd/compile: fix no-op instruction used by s390x
CL 152537 introduced a new use for ginsnop, the arch-dependent
routine that generates nops. The previous s390x nop clobbered flags.
It turns out the previous uses of this nop did not require flags
to be preserved, but the new use does.
Use a real nop: the 4-byte preferred nop.
Fixes #29453
Change-Id: I95310dfdd831932e26f5d5b6608324687f4c3162
Reviewed-on: https://go-review.googlesource.com/c/155926 Reviewed-by: Michael Munday <mike.munday@ibm.com>
David Chase [Wed, 2 Jan 2019 21:52:49 +0000 (16:52 -0500)]
cmd/compile: Update ssa/debug_test reference files for delve and gdb
Recent changes to compiler backtraces perturbed the line
number assignment, some better, some worse, probably net
worse. For purposes of passing the long tests, update the
reference files (delve's file was also stale).
TODO: Figure out a less delicate way to locate statement
boundaries for 1.13.
Austin Clements [Mon, 31 Dec 2018 01:04:16 +0000 (20:04 -0500)]
runtime: don't spin in checkPut if non-preemptible
Currently it's possible for the runtime to deadlock if checkPut is
called in a non-preemptible context. In this case, checkPut may spin,
so it won't leave the non-preemptible context, but the thread running
gcMarkDone needs to preempt all of the goroutines before it can
release the checkPut spin loops.
Fix this by returning from checkPut if it's called under any of the
conditions that would prevent gcMarkDone from preempting it. In this
case, it leaves a note behind that this happened; if the runtime does
later detect left-over work it can at least indicate that it was
unable to catch it in the act.
Cherry Zhang [Wed, 2 Jan 2019 17:27:55 +0000 (12:27 -0500)]
cmd/compile: fix deriving from x+d >= w on overflow in prove pass
In the case of x+d >= w, where d and w are constants, we are
deriving x is within the bound of min=w-d and max=maxInt-d. When
there is an overflow (min >= max), we know only one of x >= min
or x <= max is true, and we derive this by excluding the other.
When excluding x >= min, we did not consider the equal case, so
we could incorrectly derive x <= max when x == min.
Fixes #29502.
Change-Id: Ia9f7d814264b1a3ddf78f52e2ce23377450e6e8a
Reviewed-on: https://go-review.googlesource.com/c/156019 Reviewed-by: David Chase <drchase@google.com>
Richard Musiol [Tue, 11 Dec 2018 12:59:18 +0000 (13:59 +0100)]
runtime: fix notetsleepg deadline on js/wasm
A notetsleepg may get stuck if its timeout callback gets invoked
exactly on its deadline due to low precision of nanotime. This change
fixes the comparison so it also resolves the note if the timestamps are
equal.
Updates #28975
Change-Id: I045d2f48b7f41cea0caec19b56876e9de01dcd6c
Reviewed-on: https://go-review.googlesource.com/c/153558
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Michael McLoughlin [Tue, 1 Jan 2019 01:14:54 +0000 (17:14 -0800)]
runtime: fix REFLECTMETHOD macro
Removes spurious equals sign from REFLECTMETHOD macro.
Fixes #29487
Change-Id: Iaa3d85ff57087aa79a259f28816f8b0a552536f3
Reviewed-on: https://go-review.googlesource.com/c/155927
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
whereas this is a longstanding tradition
and insofaras it is worth continuing such traditions
and notwithstanding an attempt at future-proofing
thetruthofthematter is that I have been waiting for years to send this change
so despiteallobjections I have updated the copyright year.
Yuval Pavel Zholkover [Sat, 29 Dec 2018 12:27:15 +0000 (14:27 +0200)]
syscall: revert to pre-FreeBSD 10 / POSIX-2008 timespec field names in Stat_t on FreeBSD
CL 138595 introduced the new names when the hardcoded stat8 definitions was replaced
with a cgo generated one.
Fixes #29393
Updates #22448
Change-Id: I6309958306329ff301c17344b2e0ead0cc874224
Reviewed-on: https://go-review.googlesource.com/c/155958
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Jordan Rhee [Sun, 30 Dec 2018 00:19:16 +0000 (16:19 -0800)]
runtime: use EnumTimeFormatsEx instead of EnumWindows in callback tests
Use EnumTimeFormatsEx() to test panics across callback boundaries
instead of EnumWindows(). EnumWindows() is incompatible with Go's panic
unwinding mechanism. See the associated issue for more information.
Updates #26148
Change-Id: If1dd70885d9c418b980b6827942cb1fd16c73803
Reviewed-on: https://go-review.googlesource.com/c/155923
Run-TryBot: Alex Brainman <alex.brainman@gmail.com> Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Keith Randall [Fri, 28 Dec 2018 20:43:48 +0000 (12:43 -0800)]
cmd/compile: fix racewalk{enter,exit} removal
We can't remove race instrumentation unless there are no calls,
not just no static calls. Closure and interface calls also count.
The problem in issue 29329 is that there was a racefuncenter, an
InterCall, and a racefuncexit. The racefuncenter was removed, then
the InterCall was rewritten to a StaticCall. That prevented the
racefuncexit from being removed. That caused an imbalance in
racefuncenter/racefuncexit calls, which made the race detector barf.
Work involved in getting a stack trace is divided between
runtime.Callers and runtime.CallersFrames.
Before this CL, runtime.Callers returns a pc per runtime frame.
runtime.CallersFrames is responsible for expanding a runtime frame
into potentially multiple user frames.
After this CL, runtime.Callers returns a pc per user frame.
runtime.CallersFrames just maps those to user frame info.
Entries in the result of runtime.Callers are now pcs
of the calls (or of the inline marks), not of the instruction
just after the call.
Fixes #29007
Fixes #28640
Update #26320
Change-Id: I1c9567596ff73dc73271311005097a9188c3406f
Reviewed-on: https://go-review.googlesource.com/c/152537
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: David Chase <drchase@google.com>
This rule is problematic. 1<<(32-uint32(d)) <= int32(c) meant to
say that it is true if c is greater than the largest possible
value of the right shift. But when d==1, 1<<(32-1) is negative
and results in the wrong comparison.
Max Ushakov [Fri, 21 Dec 2018 14:53:33 +0000 (17:53 +0300)]
time: return ENOENT if a zoneinfo zip file is not found
Updates #20969
Change-Id: Ibcf0bf932d5b1de67c22c63dd8514ed7a5d198fb
Reviewed-on: https://go-review.googlesource.com/c/155538
Run-TryBot: Ian Lance Taylor <iant@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
LE Manh Cuong [Fri, 21 Dec 2018 04:21:02 +0000 (11:21 +0700)]
path/filepath: walkSymlinks: return correct error for file with trailing slash
Rather than return os.ErrNotExist for /path/to/existing_file/,
walkSymLinks now returns syscall.ENOTDIR.
This is consistent with behavior of os.Lstat.
Fixes #29372
Change-Id: Id5c471d901db04b2f35d60f60a81b2a0be93cae9
Reviewed-on: https://go-review.googlesource.com/c/155597
Run-TryBot: Ian Lance Taylor <iant@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Daniel Martí [Thu, 20 Dec 2018 23:04:18 +0000 (00:04 +0100)]
cmd/go: add regression test for cryptic vcs errors
On Go 1.11.x, if one ran 'go build' on a main package within a module,
while a needed vcs program like git was missing, a confusing error would
show up:
build testmod: cannot find module for path rsc.io/quote
The error should instead point at the source of the problem, which is
the missing vcs program. Thankfully, Go 1.12 doesn't have this bug, even
though it doesn't seem like the bug was fixed directly and
intentionally.
To ensure that this particular edge case isn't broken again, add a
regression test. Piggyback on mod_vcs_missing, since it already requires
a missing vcs program and network access.
I double-checked that Go 1.11 fails this test via /usr/bin/go, which is
1.11.3 on my system:
$ PATH=~/tip/bin go test -v -run Script/mod_vcs_missing
[...]
> exec /usr/bin/go build
[stderr]
build m: cannot find module for path launchpad.net/gocheck
Fixes #28948.
Change-Id: Iff1bcf77d9f7c11d15935cb87d6f58d7981d33d2
Reviewed-on: https://go-review.googlesource.com/c/155537
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Bryan C. Mills <bcmills@google.com>
Keith Randall [Sat, 22 Dec 2018 00:36:45 +0000 (16:36 -0800)]
cmd/compile: pad zero-sized stack variables
If someone takes a pointer to a zero-sized stack variable, it can
be incorrectly interpreted as a pointer to the next object in the
stack frame. To avoid this, add some padding after zero-sized variables.
We only need to pad if the next variable in memory (which is the
previous variable in the order in which we allocate variables to the
stack frame) has pointers. If the next variable has no pointers, it
won't hurt to have a pointer to it.
Because we allocate all pointer-containing variables before all
non-pointer-containing variables, we should only have to pad once per
frame.
Fixes #24993
Change-Id: Ife561cdfdf964fdbf69af03ae6ba97d004e6193c
Reviewed-on: https://go-review.googlesource.com/c/155698
Run-TryBot: Keith Randall <khr@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Keith Randall [Fri, 21 Dec 2018 23:41:28 +0000 (15:41 -0800)]
cmd/compile: fix line number for implicitly declared method expressions
Method expressions where the method is implicitly declared have no
line number. The Error method of the built-in error type is one such
method. We leave the line number at the use of the method expression
in this case.
Fixes #29389
Change-Id: I29c64bb47b1a704576abf086599eb5af7b78df53
Reviewed-on: https://go-review.googlesource.com/c/155639
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Jay Conrod [Fri, 21 Dec 2018 18:47:20 +0000 (13:47 -0500)]
cmd/go: use cached source files in "go list -find -compiled"
When "go list" is invoked with -find, it clears the list of imports
for each package matched on the command line. This affects action IDs,
since they incorporate dependencies' action IDs. Consequently, the
build triggered by -compiled won't find sources cached by
"go build".
We can still safely cache compiled sources from multiple runs of
"go list -find -compiled" though, since cgo generated sources are not
affected by imported dependencies. This change adds a second look into
the cache in this situation.
Fixes #29371
Change-Id: Ia0ae5a403ab5d621feaa16f521e6a65ac0ae6d9a
Reviewed-on: https://go-review.googlesource.com/c/155481 Reviewed-by: Bryan C. Mills <bcmills@google.com>
Jay Conrod [Fri, 21 Dec 2018 17:23:18 +0000 (12:23 -0500)]
cmd/go: fix -n output in runtime/internal/atomic
When building runtime/internal/atomic, the toolchain writes a symabis2
file. This file is read back in, filtered, and appended to the symabis
file. This breaks with -n, since the symabis2 file is never written.
With this change, when -n is used, an equivalent "grep" command is
printed instead. The output for -x is unchanged.
Fixes #29346
Change-Id: Id25e06e06364fc6689e71660d000f09c649c4f0c
Reviewed-on: https://go-review.googlesource.com/c/155480 Reviewed-by: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Michael Anthony Knyszek [Thu, 20 Dec 2018 20:21:45 +0000 (20:21 +0000)]
runtime: skip TestLockOSThreadAvoidsStatePropagation if one can't unshare
This change splits a testprog out of TestLockOSThreadExit and makes it
its own test. Then, this change makes the testprog exit prematurely with
a special message if unshare fails with EPERM because not all of the
builders allow the user to call the unshare syscall.
Also, do some minor cleanup on the TestLockOSThread* tests.
Matthew Dempsky [Thu, 20 Dec 2018 19:10:06 +0000 (11:10 -0800)]
cmd/compile: fix ICE due to bad rune width
It was possible that
var X interface{} = 'x'
could cause a compilation failure due to having not calculated rune's
width yet. typecheck.go normally calculates the width of things, but
it doesn't for implicit conversions to default type. We already
compute the width of all of the standard numeric types in universe.go,
but we failed to calculate it for the rune alias type. So we could
later crash if the code never otherwise explicitly mentioned 'rune'.
While here, explicitly compute widths for 'byte' and 'error' for
consistency.
Kevin Burke [Tue, 25 Sep 2018 16:22:09 +0000 (09:22 -0700)]
os: clearer doc for Interrupt
I was confused by the juxtaposition of os.Interrupt docs, which are
"guaranteed to exist on all platforms" in one sentence and then
"not implemented" in the next sentence. Reading the code reveals
"not implemented" refers specifically to the implementation of
os.Process.Signal on Windows, not to the os.Interrupt variable itself.
Reword the doc to make this distinction clearer.
Fixes #27854.
Change-Id: I5fe7cddea61fa1954cef2006dc51b8fa8ece4d6e
Reviewed-on: https://go-review.googlesource.com/c/137336 Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Keith Randall [Thu, 13 Dec 2018 17:31:21 +0000 (09:31 -0800)]
cmd/compile: ignore out-of-bounds reads from readonly constants
Out-of-bounds reads of globals can happen in dead code. For code
like this:
s := "a"
if len(s) == 3 {
load s[0], s[1], and s[2]
}
The out-of-bounds loads are dead code, but aren't removed yet
when lowering. We need to not panic when compile-time evaluating
those loads. This can only happen for dead code, so the result
doesn't matter.
Fixes #29215
Change-Id: I7fb765766328b9524c6f2a1e6ab8d8edd9875097
Reviewed-on: https://go-review.googlesource.com/c/154057
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>
Tobias Klauser [Thu, 20 Dec 2018 08:38:37 +0000 (09:38 +0100)]
doc/go1.12: fix GOARCH value in Syscall18 link
Currently the link works also with the non-existing GOARCH armd64, but
let's correct in anyhow.
Change-Id: Ida647b8f9dd2f8460b019f5a23759f10a6da8e60
Reviewed-on: https://go-review.googlesource.com/c/155277 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Ian Lance Taylor [Tue, 18 Dec 2018 23:10:38 +0000 (15:10 -0800)]
net: don't accept timeouts in TestUDPZeroBytePayload
Before this CL we accepted timeouts in TestUDPZeroBytePayload to avoid
flakiness and because, according to CL 9194, the test didn't work on
some platforms. On Windows, before CL 132781, the read would always
timeout, and so since the test accepted timeouts it would pass
incorrectly. CL 132781 fixed Windows, and changed the test to not
accept timeouts in the ReadFrom case.
However, the timeout was short, and so on a loaded system the Read
might timeout not due to an error in the code, but just because the
read was not delivered. So ignoring timeouts made the test flaky, as
reported in issue #29225.
This CL tries to get to a better state by increasing the timeout to a
large value and not permitting timeouts at all. If there are systems
where the test fails, we will need to explicitly skip the test on
those systems.
Fixes #29225
Change-Id: I26863369898a69cac866b34fcb5b6ffbffab31f6
Reviewed-on: https://go-review.googlesource.com/c/154759
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Alex Brainman <alex.brainman@gmail.com> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Alex Brainman [Mon, 17 Dec 2018 09:39:48 +0000 (20:39 +1100)]
os: adjust TempDir for Z:\
If TMP environment variable is set to Z:\, TempDir returns Z:.
But Z: refers to current directory on Z:, while Z:\ refers to root
directory on Z:. Adjust TempDir to return Z:\.
Jordan Rhee [Wed, 19 Dec 2018 00:41:57 +0000 (16:41 -0800)]
runtime: use QPC to implement cputicks() on windows/arm
Tracing uses cputicks() to generate trace event timestamps. cputicks()
is expected to be a high resolution clock source. On Windows/ARM,
call QueryPerformanceCounter() which is the highest resolution clock
source available.
Michael Anthony Knyszek [Fri, 7 Dec 2018 00:07:43 +0000 (00:07 +0000)]
runtime: don't clear lockedExt on locked M when G exits
When a locked M has its G exit without calling UnlockOSThread, then
lockedExt on it was getting cleared. Unfortunately, this meant that
during P handoff, if a new M was started, it might get forked (on
most OSs besides Windows) from the locked M, which could have kernel
state attached to it.
To solve this, just don't clear lockedExt. At the point where the
locked M has its G exit, it will also exit in accordance with the
LockOSThread API. So, we can safely assume that it's lockedExt state
will no longer be used. For the case of the main thread where it just
gets wedged instead of exiting, it's probably better for it to keep
the locked marker since it more accurately represents its state.
Michael Anthony Knyszek [Wed, 19 Dec 2018 17:32:22 +0000 (17:32 +0000)]
runtime: disable TestArenaCollision on Darwin in race mode
This change disables the test TestArenaCollision on Darwin in race mode
to deal with the fact that Darwin 10.10 must use MAP_FIXED in race mode
to ensure we retain our heap in a particular portion of the address
space which the race detector needs. The test specifically checks to
make sure a manually mapped region's space isn't re-used, which is
definitely possible with MAP_FIXED because it replaces whatever mapping
already exists at a given address.
This change then also makes it so that MAP_FIXED is only used in race
mode and on Darwin, not all BSDs, because using MAP_FIXED breaks this
test for FreeBSD in addition to Darwin.
Jordan Rhee [Wed, 19 Dec 2018 00:32:09 +0000 (16:32 -0800)]
Revert "runtime: use QPC for nanotime and time.now on windows/arm"
This reverts change https://golang.org/cl/154758.
Restore the previous implementations of nanotime and time.now, which
are sufficiently high resolution and more efficient than
QueryPerformanceCounter. The intent of the change was to improve
resolution of tracing timestamps, but the change was overly broad
as it was only necessary to fix cputicks(). cputicks() is fixed in
a subsequent change.
Agniva De Sarker [Wed, 19 Dec 2018 05:03:42 +0000 (10:33 +0530)]
doc/go1.12: fix minor grammatical error
Change-Id: I767bf77aeab62f2d42239fac9d601a8e04fe860f
Reviewed-on: https://go-review.googlesource.com/c/154957 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Tobias Klauser [Wed, 19 Dec 2018 08:36:11 +0000 (09:36 +0100)]
doc/go1.12: fix typos and code formatting
Fix two typos and don't indent the go vet example.
Change-Id: Iccec56ca5decfbae45547a00115500ed13b703e1
Reviewed-on: https://go-review.googlesource.com/c/154721 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Change-Id: I3c8ba5fdb05b6b1324648622656cc10071c70a34
Reviewed-on: https://go-review.googlesource.com/c/154997 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Michael Anthony Knyszek [Tue, 18 Dec 2018 20:04:53 +0000 (20:04 +0000)]
runtime: avoid write barrier in startpanic_m
startpanic_m could be called correctly in a context where there's a
valid G, a valid M, but no P, for example in a signal handler which
panics. Currently, startpanic_m has write barriers enabled because
write barriers are permitted if a G's M is dying. However, all the
current write barrier implementations assume the current G has a P.
Therefore, in this change we disable write barriers in startpanic_m,
remove the only pointer write which clears g.writebuf, and fix up gwrite
to ignore the writebuf if the current G's M is dying, rather than
relying on it being nil in the dying case.
Jordan Rhee [Tue, 18 Dec 2018 20:54:23 +0000 (12:54 -0800)]
runtime: use QPC for nanotime and time.now on windows/arm
The previous implementation of nanotime and time.now used a time source
that was updated on the system clock tick, which has a maximum
resolution of about 1ms. On 386 and amd64, this time source maps to
the system performance counter, so has much higher resolution.
On ARM, use QueryPerformanceCounter() to get a high resolution timestamp.
Elias Naur [Tue, 18 Dec 2018 20:32:48 +0000 (21:32 +0100)]
doc/go1.12: note that syscall.Getdirentries is no longer supported on iOS
Change-Id: I4277f4130b460b42c5b51fd5a5e07f6c0e62163b
Reviewed-on: https://go-review.googlesource.com/c/154720 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Kevin Burke [Mon, 17 Dec 2018 00:37:07 +0000 (00:37 +0000)]
os: show how to print permission bits in octal
Permission bits are most commonly viewed in string form (rwx-- etc) or
in octal form (0755), but the latter is relatively rare in Go.
Demonstrate how to print a FileMode in readable octal format.
Change-Id: I41feb801bcecb5077d4eabafdea27c149fc179a1
Reviewed-on: https://go-review.googlesource.com/c/154423
Run-TryBot: Ian Lance Taylor <iant@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Michael Anthony Knyszek [Tue, 11 Dec 2018 22:03:04 +0000 (22:03 +0000)]
runtime: call mmap with MAP_FIXED on BSDs in race mode
This change makes it so that reserving more of the address space for the
heap calls mmap with MAP_FIXED in race mode. Race mode requires certain
guarantees on where the heap is located in the address space, and on
Darwin 10.10 it appears that the kernel may end up ignoring the hint
quite often (#26475). Using MAP_FIXED is relatively OK in race mode
because nothing else should be mapped in the memory region provided by
the initial hints.