androidtest.bash: drop noisy adb sync output

LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://codereview.appspot.com/138070043
go/parser: initialize file set even in only some tests are run

Without this fix, some tests crashed (e.g. go test -run Invalid).

LGTM=adonovan
R=adonovan
CC=golang-codereviews
https://codereview.appspot.com/133580043
runtime: reconvert sigqueue.goc from C to Go

The original conversion in CL 132090043 cut up
the function in an attempt to avoid converting most
of the code to Go. This contorts the control flow.

While debugging the onM signal stack bug,
I reconverted sigqueue.goc in its entirety.
This restores the original control flow, which is
much easier to understand.

The current conversion is correct, it's just complex
and will be hard to maintain. The new one is as
readable as the original code.

I uploaded sigqueue.goc as the initial copy of
sigqueue.go in the CL, so if you view the diffs
of sigqueue.go comparing against patch set 2 [sic]
it will show the actual starting point.

For example:
https://codereview.appspot.com/136160043/diff2/20001:60001/src/pkg/runtime/sigqueue.go

LGTM=dvyukov, iant
R=golang-codereviews, dvyukov, iant
CC=golang-codereviews, khr, r
https://codereview.appspot.com/136160043
runtime: use C for readgstatus, goroutine status values

When this code was written, there was no way for Go to
reuse the C function and enum values. Now there is.

LGTM=bradfitz
R=rlh, bradfitz
CC=dvyukov, golang-codereviews, iant, khr, r
https://codereview.appspot.com/139150045
runtime: convert cgocall to Go

LGTM=khr, rsc
R=golang-codereviews, khr, rsc
CC=golang-codereviews
https://codereview.appspot.com/131670043

Committer: Russ Cox <rsc@golang.org>
runtime: make more functions safe for Go

Convert no-op race functions.
Everything else is tiny and gets NOSPLITs.

After this, all that is left on darwin is sysAlloc, panic, and gothrow (all pending).
There may be system-specific calls in other builds.

LGTM=iant
R=golang-codereviews, iant
CC=dvyukov, golang-codereviews, khr, r
https://codereview.appspot.com/140240044
go/parser: fix "zero day" parse error

(a b string, ok bool) is not a valid signature

Fixes issue 8656.

LGTM=adonovan
R=adonovan
CC=golang-codereviews
https://codereview.appspot.com/137140043
cmd/api: don't depend on os/user or USER to check api

The -nocgo builder failed because it has cgo disabled
as well as no USER environment variable:
http://build.golang.org/log/2250abb82f5022b72a12997b8ff89fcdeff094c9

# Checking API compatibility.
Error getting current user: user: Current not implemented on linux/amd64
exit status 1

Don't require the environment variable here.

LGTM=minux
R=dave, adg, minux
CC=golang-codereviews
https://codereview.appspot.com/140290043
runtime: more C to Go conversion adjustments

Mostly NOSPLIT additions.
Had to rewrite atomic_arm.c in Go because it calls lock,
and lock is too complex.

With this CL, I find no Go -> C calls that can split the stack
on any system except Solaris and Windows.

Solaris and Windows need more work and will be done separately.

LGTM=iant, dave
R=golang-codereviews, bradfitz, iant, dave
CC=dvyukov, golang-codereviews, khr, r
https://codereview.appspot.com/137160043
runtime: mark sysAlloc nosplit

sysAlloc is the only mem function called from Go.

LGTM=iant, khr
R=golang-codereviews, khr, 0intro, iant
CC=dvyukov, golang-codereviews, r
https://codereview.appspot.com/139210043
cmd/dist: make textflag.h available in runtime, avoid android/linux conflicts

1) cmd/dist was copying textflag.h to the build include directory,
but only after compiling package runtime. So other packages could
use it, just not runtime. Copy earlier, so that runtime can use it too.

2) We decided for android that anything marked linux is also included
in the build. The generated linux-specific files in cmd/dist must therefore
have explicit +build !android tags, or else you can't have simultaneous
linux/arm and android/arm builds in a single client. The tag was already
there for at least one file, but it was missing from many others.

LGTM=r
R=r
CC=golang-codereviews
https://codereview.appspot.com/134500043
cmd/dist: another attempt at textflag.h

The old change worked fine in my client, but my client
must not have been in a completely clean state.

TBR=r
CC=golang-codereviews
https://codereview.appspot.com/138100043
runtime: do not stop traceback at onM

Behavior before this CL:

1. If onM is called on a g0 stack, it just calls the given function.

2. If onM is called on a gsignal stack, it calls badonm.

3. If onM is called on a curg stack, it switches to the g0 stack
and then calls the function.

In cases 1 and 2, if the program then crashes (and badonm always does),
we want to see what called onM, but the traceback stops at onM.
In case 3, the traceback must stop at onM, because the g0
stack we are renting really does stop at onM.

The current code stops the traceback at onM to handle 3,
at the cost of making 1 and 2 crash with incomplete traces.

Change traceback to scan past onM but in case 3 make it look
like on the rented g0 stack, onM was called from mstart.
The traceback already knows that mstart is a top-of-stack function.

Alternate fix at CL 132610043 but I think this one is cleaner.
This CL makes 3 the exception, while that CL makes 1 and 2 the exception.

Submitting TBR to try to get better stack traces out of the
freebsd/amd64 builder, but happy to make changes in a
followup CL.

TBR=khr
R=khr
CC=golang-codereviews
https://codereview.appspot.com/133620043
runtime: use new #include "textflag.h"

I did this just to clean things up, but it will be important
when we drop the pkg directory later.

LGTM=bradfitz
R=r, bradfitz
CC=golang-codereviews
https://codereview.appspot.com/132600043
syscall: in linux/arm Syscall, zero R3, R4, R5

The general kernel system call interface
takes 6 arguments: R0, R1, R2, R3, R4, R5.

Syscall is for calls that only need 3.
The amd64 and 386 versions zero the extra arg registers,
but the arm version does not.

func utimensat calls Syscall with 3 arguments.
The kernel expects a 4th argument.
That turns out to be whatever is in R3 at the time of the call.
CL 137160043 changed various pieces of code and apparently
changed the value left in R3 at the time of utimensat's Syscall.
This causes the kernel to return EINVAL.

Change linux/arm Syscall to zero R3, R4, R5, so that calls will
behave deterministically, even if they pass too few arguments.

Arguably, utimensat could be fixed too, but the predictable
zeroing is certainly worth doing, and once done utimensat's
use of Syscall is fine.

Fixes arm build.

TBR=bradfitz
CC=golang-codereviews
https://codereview.appspot.com/141080043
runtime: use cas loop to coordinate with sigprof

sigprof and setcpuprofilerate coordinate the enabling/disabling
of the handler using a Mutex. This has always been a bit dodgy:
setcpuprofilerate must be careful to turn off signals before acquiring
the lock to avoid a deadlock.

Now the lock implementations use onM, and onM isn't okay on the
signal stack. We know how to make it okay, but it's more work than
is probably worth doing.

Since this is super-dodgy anyway, replace the lock with a simple
cas loop. It is only contended if setcpuprofilerate is being called,
and that doesn't happen frequently enough to care about the
raw speed or about using futexes/semaphores.

TBR to fix freebsd/amd64 and dragonfly/amd64 builds.
Happy to make changes in a follow-up CL.

TBR=dvyukov
CC=golang-codereviews
https://codereview.appspot.com/141080044
runtime: convert panic/recover to Go

created panic1.go just so diffs were available.
After this CL is in, I'd like to move panic.go -> defer.go
and panic1.go -> panic.go.

LGTM=rsc
R=rsc, khr
CC=golang-codereviews
https://codereview.appspot.com/133530045

Committer: Russ Cox <rsc@golang.org>
net: temporarily skip TestAcceptIgnoreSomeErrors

Update issue 8662

LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://codereview.appspot.com/138120043

Committer: Brad Fitzpatrick <bradfitz@golang.org>
runtime: clean up sigqueue.go

Minor changes to make logic clearer.
Observed while working on the conversion.

LGTM=iant, dvyukov
R=dvyukov, iant
CC=golang-codereviews
https://codereview.appspot.com/140250043
runtime: handle nil ptr load/store in arm software floating point

We cannot let a real panic start there, because there is C code
on the stack, and worse, there is an assembly frame with a
saved copy of the registers and we have no idea which ones
are pointers.

Instead, detect the nil ptr load/store and return out of the C
and assembly into a stub that will start the call to sigpanic.

Fixes GOARM=5 build.

LGTM=iant
R=golang-codereviews, iant
CC=dave, golang-codereviews, minux, r
https://codereview.appspot.com/138130043