It's fairly common to call cgo functions with conversions to
unsafe.Pointer or other C types.  Apply the simpler checking of address
expressions when possible when the address expression occurs within a
type conversion.

Change-Id: I5187d4eb4d27a6542621c396cad9ee4b8647d1cd
Reviewed-on: https://go-review.googlesource.com/18391
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

Go 1.5 and earlier said "day out of range".
As part of working on this code it morphed into "day of month out of range".
To avoid churn in the output restore the old text.

This fixes some tests reported privately.

Change-Id: If179676cd49f9a471a9441fec2f5220c85eb0799
Reviewed-on: https://go-review.googlesource.com/18386Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #13564.

Change-Id: I30c827ef4a112fee21b8493a67d0227109e35072
Reviewed-on: https://go-review.googlesource.com/18384Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Document the three GODEBUG environment variables in the package doc.

Updates the bundled http2 to x/net git rev 415f1917
for https://golang.org/cl/18372.

Fixes #13611

Change-Id: I3116c5d7de70d3d15242d7198f3758b1fb7d94b9
Reviewed-on: https://go-review.googlesource.com/18373Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

I thought there was still work to do in http2 for this, but I guess
not: the work for parsing them is in net/url (used by http2) and the
handling of OPTIONS * is already in net/http serverHandler, also used
by http2.

But keep the tests.

Change-Id: I566dd0a03cf13c9ea8e735c6bd32d2c521ed503b
Reviewed-on: https://go-review.googlesource.com/18368Reviewed-by: Blake Mizerany <blake.mizerany@gmail.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>

Adding the evconst(n) call for OANDAND and OOROR in
golang.org/cl/18262 was originally just to parallel the above iscmp
branch, but upon further inspection it seemed odd that removing it
caused test/fixedbugs/issue6671.go's

    var b mybool
    // ...
    b = bool(true) && true // ERROR "cannot use"

to start failing (i.e., by not emitting the expected "cannot use"
error).

The problem is that evconst(n)'s settrue and setfalse paths always
reset n.Type to idealbool, even for logical operators where n.Type
should preserve the operand type.  Adding the evconst(n) call for
OANDAND/OOROR inadvertantly worked around this by turning the later
evconst(n) call at line 2167 into a noop, so the "n.Type = t"
assignment at line 739 would preserve the operand type.

However, that means evconst(n) was still clobbering n.Type for ONOT,
so declarations like:

    const _ bool = !mybool(true)

were erroneously accepted.

Update #13821.

Change-Id: I18e37287f05398fdaeecc0f0d23984e244f025da
Reviewed-on: https://go-review.googlesource.com/18362
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

f90b48e0 intended to require the stack barrier lock in all cases of
sigprof that walked the user stack, but got it wrong. In particular,
if sp < gp.stack.lo || gp.stack.hi < sp, tracebackUser would be true,
but we wouldn't acquire the stack lock. If it then turned out that we
were in a cgo call, it would walk the stack without the lock.

In fact, the whole structure of stack locking is sigprof is somewhat
wrong because it assumes the G to lock is gp.m.curg, but all three
gentraceback calls start from potentially different Gs.

To fix this, we lower the gcTryLockStackBarriers calls much closer to
the gentraceback calls. There are now three separate trylock calls,
each clearly associated with a gentraceback and the locked G clearly
matches the G from which the gentraceback starts. This actually brings
the sigprof logic closer to what it originally was before stack
barrier locking.

This depends on "runtime: increase assumed stack size in
externalthreadhandler" because it very slightly increases the stack
used by sigprof; without this other commit, this is enough to blow the
profiler thread's assumed stack size.

Fixes #12528 (hopefully for real this time!).

For the 1.5 branch, though it will require some backporting. On the
1.5 branch, this will *not* require the "runtime: increase assumed
stack size in externalthreadhandler" commit: there's no pcvalue cache,
so the used stack is smaller.

Change-Id: Id2f6446ac276848f6fc158bee550cccd03186b83
Reviewed-on: https://go-review.googlesource.com/18328
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

On Windows, externalthreadhandler currently sets the assumed stack
size for the profiler thread and the ctrlhandler threads to 8KB. The
actual stack size is determined by the SizeOfStackReserve field in the
binary set by the linker, which is currently at least 64KB (and
typically 128KB).

It turns out the profiler thread is running within a few words of the
8KB-(stack guard) bound set by externalthreadhandler. If it overflows
this bound, morestack crashes unceremoniously with an access
violation, which we then fail to handle, causing the whole process to
exit without explanation.

To avoid this problem and give us some breathing room, increase the
assumed stack size in externalthreadhandler to 32KB (there's some
unknown amount of stack already in use, so it's not safe to increase
this all the way to the reserve size).

We also document the relationships between externalthreadhandler and
SizeOfStackReserve to make this more obvious in the future.

Change-Id: I2f9f9c0892076d78e09827022ff0f2bedd9680a9
Reviewed-on: https://go-review.googlesource.com/18304
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Minux Ma <minux@golang.org>

If a sigprof happens during a cgo call, we traceback from the entry
point of the cgo call. However, if the SP is outside of the G's stack,
we'll then ignore this traceback, even if it was successful, and
overwrite it with just _ExternalCode.

Fix this by accepting any successful traceback, regardless of whether
we got it from a cgo entry point or from regular Go code.

Fixes #13466.

Change-Id: I5da9684361fc5964f44985d74a8cdf02ffefd213
Reviewed-on: https://go-review.googlesource.com/18327
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

Change-Id: Ideb4bd9ffb1b5f1aef7d94ff791a262f54a650d5
Reviewed-on: https://go-review.googlesource.com/18344Reviewed-by: Ian Lance Taylor <iant@golang.org>

net has GODEBUG text already.
net/http still needs it (leaving for Brad).

For #13611.

Change-Id: Icea1027924a23a687cbbe4001985e8c6384629d7
Reviewed-on: https://go-review.googlesource.com/18346Reviewed-by: Ian Lance Taylor <iant@golang.org>

Updates http2 to x/net git rev 520af5de654d for
https://golang.org/cl/18370

Fixes #13659

Change-Id: I920eaff6036ac22c500a97449826c6b12f873d7f
Reviewed-on: https://go-review.googlesource.com/18371
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>

Change-Id: I995ac0559f89110662d79d136d710ef3a0bb1505
Reviewed-on: https://go-review.googlesource.com/18351Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #13731.

Change-Id: Iaf70a8b41c947f0d86013808564112ab676136e3
Reviewed-on: https://go-review.googlesource.com/18345Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

Fixes #13358

Change-Id: I57ed50c2610cab11fb3d9749f9e7d4a37daa7977
Reviewed-on: https://go-review.googlesource.com/18276Reviewed-by: Russ Cox <rsc@golang.org>

Now there are ARM downloads too.

Change-Id: I236381508c69d56748e672d184b92caa715e81ae
Reviewed-on: https://go-review.googlesource.com/18342Reviewed-by: Andrew Gerrand <adg@golang.org>

Update bundled http2 to git rev d1ba260648 (https://golang.org/cl/18288).

Fixes the flaky TestTransportAndServerSharedBodyRace_h2.

Also adds some debugging to TestTransportAndServerSharedBodyRace_h2
which I hope won't ever be necessary again, but I know will be.

Fixes #13556

Change-Id: Ibcf2fc23ec0122dcac8891fdc3bd7f8acddd880e
Reviewed-on: https://go-review.googlesource.com/18289Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes golang/go#12490

Change-Id: I0861e62aaa589fc63217c83e9c227c17e35cda75
Reviewed-on: https://go-review.googlesource.com/18277Reviewed-by: Russ Cox <rsc@golang.org>

After a failure on the build dashboard I tested testcarchive test 2 and
found that it failed an average of 1 in 475 runs on my laptop.  With
this change it ran over 50,000 times without failing.  I bumped up the
other iteration limits to correspond.

Change-Id: I0155c68161a2c2a09ae25c91e9269f1e8702628d
Reviewed-on: https://go-review.googlesource.com/18309
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Simply checking the exit code of `git rev-parse --git-dir` should
suffice here, but that requires deviating from the infrastructure
provided by `run`, so I've left that for a future change.

Originally by Tamir Duberstein but updated by iant & rsc to add
the filepath.Join logic.

Fixes #11211 (again).

Change-Id: I6d29b5ae39ba456088ae1fb5d41014cb91c86897
Reviewed-on: https://go-review.googlesource.com/18323Reviewed-by: Ian Lance Taylor <iant@golang.org>

The flag is already named -insecure. Make it more so.

If we're willing to accept HTTP, it's not much worse to accept
HTTPS man-in-the-middle attacks too. This allows servers
with self-signed certificates to work.

Fixes #13197.

Change-Id: Ia5491410bc886da0a26ef3bce4bf7d732f5e19e4
Reviewed-on: https://go-review.googlesource.com/18324Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: Idf02428591f61dc58f654fdaf0e3a55f8b8a1060
Reviewed-on: https://go-review.googlesource.com/18350Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Read zip files that contain only 64-bit header offset, not 64-bit sizes.
Fixes #13367.

Read zip files that contain completely unexpected Extra fields,
provided we do not need to find 64-bit size or header offset information there.
Fixes #13166.

Write zip file entries with 0xFFFFFFFF uncompressed data bytes
correctly (must use zip64 header, since that's the magic indicator).
Fixes new TestZip64EdgeCase. (Noticed while working on the CL.)

Change-Id: I84a22b3995fafab8052b99de8094a9f35a25de5b
Reviewed-on: https://go-review.googlesource.com/18317Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #13673.

Change-Id: I60d1603ca0dfd2ae136117e0f89cee4b6fc6c3d3
Reviewed-on: https://go-review.googlesource.com/18332Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #13720.

Change-Id: I2e48454696f37db419370630f913590c435cd9f0
Reviewed-on: https://go-review.googlesource.com/18331Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>

Fixes #13845.

Change-Id: Ie83179b2d20c47a0296645d9e2fdc43271be495a
Reviewed-on: https://go-review.googlesource.com/18307Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

We were setting the signal mask of a new m to the signal mask of the m
that created it.  That failed when that m happened to be the one created
by ensureSigM, which sets its signal mask to only include the signals
being caught by os/signal.Notify.

Fixes #13164.
Update #9896.

Change-Id: I705c196fe9d11754e10bab9e9b2e7530ecdfa367
Reviewed-on: https://go-review.googlesource.com/18064Reviewed-by: Russ Cox <rsc@golang.org>

When calling a Go function on a C thread, if the C thread already has an
alternate signal stack, use that signal stack instead of installing a
new one.

Update #9896.

Change-Id: I62aa3a6a4a1dc4040fca050757299c8e6736987c
Reviewed-on: https://go-review.googlesource.com/18108Reviewed-by: Russ Cox <rsc@golang.org>

Just saw a few dragonfly failures here.

I'm tempted to preemptively add plan9 here too, but I'll wait until
I see it fail.

Change-Id: Ic99fc088dbfd1aa21f509148aee98ccfe7f640bf
Reviewed-on: https://go-review.googlesource.com/18306Reviewed-by: Russ Cox <rsc@golang.org>

Fixes #12790.

Change-Id: I0f231d198c76632c23692fc1337b57cfeafaf4c7
Reviewed-on: https://go-review.googlesource.com/18338Reviewed-by: Andrew Gerrand <adg@golang.org>

Fixes #13269.

Change-Id: I960d1825bda9d8873c2a9005872c45e4c7d30111
Reviewed-on: https://go-review.googlesource.com/18339Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #12059.

Change-Id: Ib5caf8133cd3ed888f9102dfbfeca11c506f3b5b
Reviewed-on: https://go-review.googlesource.com/18337Reviewed-by: Ian Lance Taylor <iant@golang.org>

This time with a test.
Also adjust another test to skip when hg is not present,
and delete no longer needed fixDetachedHead code.

Fixes #9032 (again).

Change-Id: I481717409e1d44b524f83c70a8dc377699d1a2a5
Reviewed-on: https://go-review.googlesource.com/18334Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #12542.

Change-Id: Icd0fa84d891d6b1feab9b4d4dd319cdf1e6d6c48
Reviewed-on: https://go-review.googlesource.com/18336Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

But also cache the previous parsed form and don't reread if the
size and modification time are both unchanged from before.

On systems with stable /etc/hosts this should result in more stat calls
but only a single parsing of /etc/hosts.

On systems with variable /etc/hosts files (like some Docker systems)
this should result in quicker adoption of changes.

Fixes #13340.

Change-Id: Iba93b204be73d6d903cd17c58038a4fcfd0952b9
Reviewed-on: https://go-review.googlesource.com/18258Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Add a couple more cases where we convert random network I/O errors
into errRequestCanceled if the request was forcefully aborted.

It failed ~1/1000 times without -race, or very easily with -race.
(due to -race randomizing some scheduling)

Fixes #11894

Change-Id: Ib1c123ce1eebdd88642da28a5948ca4f30581907
Reviewed-on: https://go-review.googlesource.com/18287Reviewed-by: Russ Cox <rsc@golang.org>

This shouldn't need to exist in general, but in practice I want something
like this a few times per year.

Change-Id: I9c220e58be44b7726f75d776f714212c570cf8bb
Reviewed-on: https://go-review.googlesource.com/18286Reviewed-by: Russ Cox <rsc@golang.org>

The old link died; replace with an archive.org copy.

Fixes #13345.

Change-Id: Ic4a7fdcf258e1ff3b4a02ecb4f237ae7db2686c7
Reviewed-on: https://go-review.googlesource.com/18335Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Adds a test that both http1 and http2's Transport send a default
User-Agent, with the same behavior.

Updates bundled http2 to golang.org/x/net git rev 1ade16a545 (for
https://go-review.googlesource.com/18285)

The http1 behavior changes slightly: if req.Header["User-Agent"] is
defined at all, even if it's nil or a zero-length slice, then the
User-Agent header is omitted. This is a slight behavior change for
http1, but is consistent with how http1 & http2 do optional headers
elsewhere (such as "Date", "Content-Type"). The old behavior (set it
explicitly to "", aka []string{""}) still works as before. And now
there are even tests.

Fixes #13685

Change-Id: I5786a6913b560de4a5f1f90e595fe320ff567adf
Reviewed-on: https://go-review.googlesource.com/18284
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

The textual export data generated by gc sometimes contains forward
references of packages. In rare cases such forward-referenced packages
were not created when needed because no package name was present.

Create unnamed packages in this case and set the name later when it
becomes known.

Fixes #13566.

Change-Id: I193e0ec712e874030b194ab8ecb3fca140f7997a
Reviewed-on: https://go-review.googlesource.com/18301Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>