broke api check everywhere

««« original CL description
runtime: fix openbsd build

LGTM=iant
R=iant, minux
CC=golang-codereviews, jsing
https://golang.org/cl/135230043

»»»

TBR=mdempsky
CC=golang-codereviews
https://golang.org/cl/137010043

Speed improvements via code cleanup, and changes to make go dns behave more like glibc resolver.  See https://groups.google.com/forum/#!topic/golang-dev/lV-0aHqxVeo

Fixes #6579.

Benchmark results on linux/amd64

benchmark                                  old ns/op    new ns/op    delta
BenchmarkGoLookupIP                          4831903      2572937  -46.75%
BenchmarkGoLookupIPNoSuchHost               10114105      2419641  -76.08%
BenchmarkGoLookupIPWithBrokenNameServer  20007735624   5004490730  -74.99%

benchmark                                 old allocs   new allocs    delta
BenchmarkGoLookupIP                              287          288    0.35%
BenchmarkGoLookupIPNoSuchHost                    204          102  -50.00%
BenchmarkGoLookupIPWithBrokenNameServer          410          358  -12.68%

benchmark                                  old bytes    new bytes    delta
BenchmarkGoLookupIP                            13181        13271    0.68%
BenchmarkGoLookupIPNoSuchHost                  17260         8714  -49.51%
BenchmarkGoLookupIPWithBrokenNameServer        28160        22432  -20.34%

LGTM=mikioh.mikioh
R=golang-codereviews, mikioh.mikioh, bradfitz, josharian, abursavich
CC=golang-codereviews
https://golang.org/cl/128820043

LGTM=iant
R=iant, minux
CC=golang-codereviews, jsing
https://golang.org/cl/135230043

Avoids a conflict between the type and function sigaltstack.

LGTM=crawshaw
R=rsc, crawshaw
CC=golang-codereviews
https://golang.org/cl/138920043

preparing for the syscall package freeze.
the change for issue 8218 is only applied to go.sys/unix.

««« original CL description
syscall: implement setresuid(2) and setresgid(2) on OpenBSD/FreeBSD/DragonflyBSD

Fixes #8218.

LGTM=iant
R=golang-codereviews, iant, minux
CC=golang-codereviews
https://golang.org/cl/107150043

»»»

LGTM=r
R=r, iant, golang-codereviews
CC=golang-codereviews
https://golang.org/cl/138840044

Prevents non-rooted queries with > ndots dots from being tried twice on error.
Fixes #8616.

Benchmark results on linux/amd64
benchmark                        old ns/op    new ns/op    delta
BenchmarkGoLookupIPNoSuchHost      8212394      4413293  -46.26%

benchmark                       old allocs   new allocs    delta
BenchmarkGoLookupIPNoSuchHost          216          108  -50.00%

benchmark                        old bytes    new bytes    delta
BenchmarkGoLookupIPNoSuchHost        17460         8726  -50.02%

LGTM=iant, mikioh.mikioh
R=golang-codereviews, iant, mikioh.mikioh
CC=golang-codereviews
https://golang.org/cl/137870043

It is anyway, just an allocated one.
Giving it a sized type makes Go access nicer.

LGTM=iant
R=dvyukov, iant
CC=golang-codereviews
https://golang.org/cl/139960043

LGTM=r, iant
R=golang-codereviews, r, iant
CC=dvyukov, golang-codereviews, khr
https://golang.org/cl/139930043

I had to rename Kevent and Sigaction to avoid the functions of the
same (lowercase) name.

LGTM=iant, r
R=golang-codereviews, r, iant, aram.h
CC=dvyukov, golang-codereviews, khr
https://golang.org/cl/140740043

Signer is an interface to support opaque private keys.
These keys typically result from being kept in special hardware
(i.e. a TPM) although sometimes operating systems provide a
similar interface using process isolation for security rather
than hardware boundaries.

This changes provides interfaces for representing them and
alters crypto/tls so that client certificates can use
opaque keys.

LGTM=bradfitz
R=bradfitz
CC=golang-codereviews, jdeprez
https://golang.org/cl/114680043

Needless except that the api tool complains. We could fix that issue instead.

TBR=bradfitz
R=golang-codereviews
CC=golang-codereviews
https://golang.org/cl/133290043

Run it right before main.init.
There is still some runtime initialization that
happens before runtime.init, and some of that
may call into Go code (for example to acquire locks)
so this timing is not perfect, but I believe it is the
best we can do.

This came up because global variables intialized
to func values are done in the generated init code,
not in the linker.

LGTM=dvyukov
R=dvyukov
CC=golang-codereviews, iant, khr, r
https://golang.org/cl/135210043

As part of the translation of the runtime, we need to rewrite
C printf calls to Go print calls. Consider this C printf:

        runtime·printf("[signal %x code=%p addr=%p pc=%p]\n",
                g->sig, g->sigcode0, g->sigcode1, g->sigpc);

Today the only way to write that in Go is:

        print("[signal ")
        printhex(uint64(g->sig))
        print(" code=")
        printhex(uint64(g->sigcode0))
        print(" addr=")
        printhex(uint64(g->sigcode1))
        print(" pc=")
        printhex(uint64(g->sigpc))
        print("]\n")

(That's nearly exactly what runtime code looked like in C before
I added runtime·printf.)

This CL recognizes the unexported type runtime.hex as an integer
that should be printed in hexadecimal instead of decimal.
It's a little kludgy, but it's restricted to package runtime.
Other packages can define type hex with no effect at all.

Now we can translate that original printf as the more compact:

        print("[signal ", hex(g->sig), " code=", hex(g->sigcode0),
                " addr=", hex(g->sigcode1), " pc=", hex(g->sigpc), "]\n")

LGTM=r, iant
R=r, iant
CC=golang-codereviews
https://golang.org/cl/133220043

LGTM=rsc, dave
R=minux, rsc, remyoudompheng, dave
CC=golang-codereviews
https://golang.org/cl/133790043

ErrorContext now has all the information it needs from the Node,
rather than depending on the template that contains it. This makes
it easier for html/template to generate correct locations in its
error messages.

Updated html/template to use this ability where it is easy, which is
not everywhere, but more work can probably push it through.

Fixes #8577.

LGTM=adg
R=golang-codereviews, adg
CC=golang-codereviews
https://golang.org/cl/130620043

Remove C version of GC.
Convert freeOSMemory to Go.
Restore g0 check in GC.
Remove unknownGCPercent check in GC,
it's initialized explicitly now.

LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews, khr
https://golang.org/cl/139910043

Breaks on Plan 9, apparently.
The other systems must not run sprintf during all.bash.
I'd write a test but it's all going away.

TBR=r
CC=0intro, golang-codereviews
https://golang.org/cl/133260044

Convert them to Go in the process.

LGTM=dvyukov, dave
R=khr, dvyukov, rsc, dave
CC=golang-codereviews
https://golang.org/cl/131600043

I've started with just one function with 8 arguments,
but stdcall is called from nosplit functions
and 8 args overflow nosplit area.

LGTM=aram, alex.brainman
R=golang-codereviews, aram, alex.brainman, dave
CC=golang-codereviews, iant, khr, rsc
https://golang.org/cl/135090043

PNG filters are applied to get better compression ratio.
It does not make sense to apply them if we are not going
to compress.

LGTM=nigeltao
R=nigeltao
CC=golang-codereviews
https://golang.org/cl/137830043

Also fix a bunch of bugs:
1. Accesses to last_gc must be atomic (it's int64).
2. last_gc still can be 0 during first checks in sysmon, check for 0.
3. forcegc.g can be unitialized when sysmon accesses it:
        forcegc.g is initialized by main goroutine (forcegc.g = newproc1(...)),
        and main goroutine is unsynchronized with both sysmon and forcegc goroutine.
        Initialize forcegc.g in the forcegc goroutine itself instead.

LGTM=khr
R=golang-codereviews, khr
CC=golang-codereviews, rsc
https://golang.org/cl/136770043

LGTM=dave
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/139890043

LGTM=bradfitz, rsc
R=golang-codereviews, bradfitz, rsc
CC=golang-codereviews
https://golang.org/cl/135150043

LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/126450043

LGTM=iant
R=golang-codereviews, iant
CC=dvyukov, golang-codereviews, khr, r
https://golang.org/cl/135930043

Update #8612

LGTM=minux
R=golang-codereviews, minux
CC=golang-codereviews
https://golang.org/cl/135170043

Clang 3.2 and older (as shipped with OS X Mountain Lion and older)
outputs ambiguous DWARF debug info that makes it impossible for us to
reconstruct accurate type information as required for this test.

Fixes #8611.

LGTM=rsc
R=r, rsc, minux
CC=golang-codereviews
https://golang.org/cl/135990043

Shrinks the text segment size by about 1.5% for the "go", "gofmt",
and "camlistored" commands on linux/amd64.

Before:
$ size go gofmt camlistored
   text	   data	    bss	    dec	    hex	filename
6506842	 136996	 105784	6749622	 66fdb6	go
2376046	  85232	  90984	2552262	 26f1c6	gofmt
17051050	 190256	 130320	17371626	10911ea	camlistored

After:
$ size go gofmt camlistored
   text	   data	    bss	    dec	    hex	filename
6403034	 136996	 105784	6645814	 656836	go
2331118	  85232	  90984	2507334	 264246	gofmt
16842586	 190256	 130320	17163162	105e39a	camlistored

Fixes #8604.

LGTM=rsc
R=golang-codereviews, bradfitz, rsc
CC=golang-codereviews
https://golang.org/cl/137790043

LGTM=0intro, rsc
R=rsc, 0intro
CC=golang-codereviews
https://golang.org/cl/132320043

This is a reapplication of CL 93520045 (changeset 5012df7fac58)
since that was lost during the move to an internal package.

LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/134020043

LGTM=r
R=golang-codereviews, r
CC=golang-codereviews
https://golang.org/cl/129650043

LGTM=r
R=golang-codereviews, r
CC=golang-codereviews
https://golang.org/cl/137750043

LGTM=r
R=golang-codereviews, r
CC=golang-codereviews
https://golang.org/cl/132230043

LGTM=r
R=golang-codereviews, r
CC=golang-codereviews
https://golang.org/cl/134940043

In revision 05c3fee13eb3, openbsd/386's tfork implementation was
accidentally changed in one instruction from using the "params"
parameter to using the "psize" parameter.

While here, OpenBSD's __tfork system call returns a pid_t which is an
int32 on all OpenBSD architectures, so change runtime.tfork's return
type from int64 to int32 and update the assembly implementations
accordingly.

LGTM=iant
R=rsc, iant
CC=golang-codereviews, jsing
https://golang.org/cl/133190043

LGTM=dvyukov
R=golang-codereviews, dvyukov, khr
CC=golang-codereviews
https://golang.org/cl/124630043

Package addition.

PositionFor permits access to both, positions
adjusted by //line comments (like the Position
accessors), and unadjusted "raw" positions
unaffected by //line comments.

Raw positions are required for correct formatting
of source code via go/printer which until now had
to manually fix adjusted positions.

Fixes #7702.

LGTM=adonovan
R=adonovan
CC=golang-codereviews
https://golang.org/cl/135110044

Only grab the lock once, don't allocate, add more tests.

LGTM=ruiu
R=ruiu, josharian
CC=golang-codereviews
https://golang.org/cl/139780043

Follow-up to https://golang.org/cl/107020044/
Also add a little comment.

LGTM=ruiu, josharian
R=josharian, ruiu
CC=golang-codereviews
https://golang.org/cl/139760043

LGTM=bradfitz
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/139770043