This eliminates ~75% of the nil checks being emitted,
on all architectures. We can do better, but we need
a bit more general support from the compiler, and
I don't want to do that so close to Go 1.2.
What's here is simple but effective and safe.

A few small code generation cleanups were required
to make the analysis consistent on all systems about
which nil checks are omitted, at least in the test.

Fixes #6019.

R=ken2
CC=golang-dev
https://golang.org/cl/13334052

47ec7a68b1a2 added support for ECDSA ciphersuites but didn't alter the
cipher suite selection to take that into account. Thus Go servers could
try and select an ECDSA cipher suite while only having an RSA
certificate, leading to connection failures.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/13239053

In particular document that the Go tool will look for certain
file extensions and compile with them with either the C or the
C++ compiler.

Fixes #6393.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/13733043

The root cause of the panic reported in https://code.google.com/p/go/issues/detail?id=5980
is that parse's Tree.Text wasn't being copied during the clone.

Fix this by adding and using a Copy method for parse.Tree.

Fixes #5980.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/12420044

Update #5764

Like Tribbles, the more you kill, the more spring up in their place.

R=rsc
CC=golang-dev
https://golang.org/cl/13324049

This interface is required to use the PCDATA interface
implemented in Go 1.2.  While initially entirely private, the
FUNCDATA side of the interface has been made public.  This
change completes the FUNCDATA/PCDATA interface.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/13735043

A new transformation during walk turns append calls
into a combination of growslice and memmove.

benchmark                     old ns/op    new ns/op    delta
BenchmarkAppend                     141          141   +0.00%
BenchmarkAppend1Byte                 18           11  -39.56%
BenchmarkAppend4Bytes                19           10  -42.63%
BenchmarkAppend7Bytes                18           10  -42.16%
BenchmarkAppend8Bytes                18           10  -40.44%
BenchmarkAppend15Bytes               19           11  -41.67%
BenchmarkAppend16Bytes               19           11  -41.97%
BenchmarkAppend32Bytes               23           14  -38.82%
BenchmarkAppendStr1Byte              14           10  -23.78%
BenchmarkAppendStr4Bytes             14           11  -21.13%
BenchmarkAppendStr8Bytes             14           10  -25.17%
BenchmarkAppendStr16Bytes            19           11  -41.45%
BenchmarkAppendStr32Bytes            18           14  -19.44%
BenchmarkAppendSpecialCase           62           63   +1.77%

R=golang-dev, khr, cshapiro, rsc, dave
CC=golang-dev
https://golang.org/cl/12815046

Hide container symbols like text and etext so that
the individual pieces inside are shown instead.
For example, if text and main.init have the same
address, it was a toss-up which name was printed.

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/13722046

The code for call site-specific pointer bitmaps was not ready in time,
but the zeroing required without it is too expensive to use by default.
We will have to wait for precise collection of stack frames until Go 1.3.

The precise collection can be re-enabled by

        GOEXPERIMENT=precisestack ./all.bash

but that will not be the default for a Go 1.2 build.

Fixes #6087.

R=golang-dev, jeremyjackins, dan.kortschak, r
CC=golang-dev
https://golang.org/cl/13677045

Fixes #5725.

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/13705044

Make the break example slightly more interesting
Update #5725
Effective Go will be updated in a separate CL.

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/13368054

With TLS 1.2, when sending client certificates the code was omitting
the new (in TLS 1.2) signature and hash fields.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/13413050

All these features have in fact been implemented.

R=rsc
CC=golang-dev
https://golang.org/cl/13419049

Fixes #6395.

R=ken2
CC=golang-dev
https://golang.org/cl/13470046

The uint64 divide function calls _mul64x32 to do a 64x32-bit multiply
and then compares the result against the 64-bit numerator.
If the result is bigger than the numerator, must use the slow path.

Unfortunately, the 64x32 produces a 96-bit product, and only the
low 64 bits were being used in the comparison. Return all 96 bits,
the bottom 64 via the original uint64* pointer, and the top 32
as the function's return value.

Fixes 386 build (broken by ARM division tests).

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/13722044

Fixes #6399.

R=ken2
CC=golang-dev
https://golang.org/cl/13253055

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/13720044

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/13700045

This CL is required for all.bat to work out of the box on
my Windows 8 laptop.

These tests either require the firewall to be turned off
or require the user to be in the Administrators group.
I don't know which.

Alex may follow up with a refinement of the test to
allow them to run if the user is in the Administrators
group.

Fixes #6392.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/13421049

Because we can, and because it otherwise might crash
the program if we think we're out of memory.

Fixes #6390.

R=golang-dev, iant, minux.ma
CC=golang-dev
https://golang.org/cl/13345048

The implementation of division in the 5 toolchain is a bit too magical.
Hide the magic from the traceback routines.

Also add a test for the results of the software divide routine.

Fixes #5805.

R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/13239052

The kernel implementation of the fast system call path,
the one invoked by the SYSCALL instruction, is broken for
restarting system calls. A C program demonstrating this is below.

Change the system calls to use INT $0x80 instead, because
that (perhaps slightly slower) system call path actually works.

I filed http://www.freebsd.org/cgi/query-pr.cgi?pr=182161.

The C program demonstrating that it is FreeBSD's fault is below.
It reports the same "Bad address" failures from wait.

#include <sys/time.h>
#include <sys/signal.h>
#include <pthread.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

static void handler(int);
static void* looper(void*);

int
main(void)
{
        int i;
        struct sigaction sa;
        pthread_cond_t cond;
        pthread_mutex_t mu;

        memset(&sa, 0, sizeof sa);
        sa.sa_handler = handler;
        sa.sa_flags = SA_RESTART;
        memset(&sa.sa_mask, 0xff, sizeof sa.sa_mask);
        sigaction(SIGCHLD, &sa, 0);

        for(i=0; i<2; i++)
                pthread_create(0, 0, looper, 0);

        pthread_mutex_init(&mu, 0);
        pthread_mutex_lock(&mu);
        pthread_cond_init(&cond, 0);
        for(;;)
                pthread_cond_wait(&cond, &mu);

        return 0;
}

static void
handler(int sig)
{
}

int
mywait4(int pid, int *stat, int options, struct rusage *rusage)
{
        int result;

        asm("movq %%rcx, %%r10; syscall"
                : "=a" (result)
                : "a" (7),
                  "D" (pid),
                  "S" (stat),
                  "d" (options),
                  "c" (rusage));
}

static void*
looper(void *v)
{
        int pid, stat, out;
        struct rusage rusage;

        for(;;) {
                if((pid = fork()) == 0)
                        _exit(0);
                out = mywait4(pid, &stat, 0, &rusage);
                if(out != pid) {
                        printf("wait4 returned %d\n", out);
                }
        }
}

Fixes #6372.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/13582047

Fixes #6312.

R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/13391049

Fixes #6367.

R=rsc, r
CC=golang-dev
https://golang.org/cl/13395047

http://golang.org/doc/go1.1#new_packages

R=r
CC=golang-dev
https://golang.org/cl/13368053

The -S flag reports symbol size, but is missing from the usage message.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/13660046

Remove "References" section.
Remove most articles and redirect to blog.golang.org.
Move /ref/spec and /ref/mem to /doc/spec and /doc/mem.
Remove duplicate links from the remaining
"Documents", "The Project", and "Help" pages.
Defer to the wiki for more links and community content.
Update command reference and mention cover tool.
Add "Pop-out" text to the front page.
Pick one of four videos at random to feature on the front page.

Fixes #2547.
Fixes #5561.
Fixes #6321.

R=r, dominik.honnef
CC=golang-dev
https://golang.org/cl/13724043

Document the semantic changes within the gc toolchain.

Also delete the mention of unbalanced right delims in template
That change was rolled back.

Absent typos, things we've forgotten, and new things that happen,
the release notes are ready.

R=golang-dev, adg, dominik.honnef
CC=golang-dev
https://golang.org/cl/13368052

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/13634044

Fixes #5821.

R=golang-dev, kamil.kisiel
CC=golang-dev
https://golang.org/cl/13720043

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/13721043

Everything is done except compiler changes and additional platforms, if any.

R=golang-dev, dominik.honnef, adg
CC=golang-dev
https://golang.org/cl/13484045

Previously, fields of type chan or func caused an error.
Now we just treat them like unexported fields and ignore them.
This makes it easier to guarantee long-term compatibilty since
a substructure from another package cannot break gob
encoding by adding a func or chan field.

Fixes #6071

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/13693043

The test 'gp == m->curg' is not valid on Windows,
because the goroutine being profiled is not from the
current m.

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/13718043

Fixes #6369.

R=dsymonds, r
CC=golang-dev
https://golang.org/cl/13708043

Fixes #5626.

R=golang-dev, dominik.honnef
CC=golang-dev
https://golang.org/cl/13702043

Just an oversight they were missing.
Fixes #6387

R=golang-dev, dominik.honnef, rsc
CC=golang-dev
https://golang.org/cl/13715043

Fake types describing the internal structure of hashmaps are
generated for use by precise GC.

Generating hash and eq functions for these fake types slows down
the build and wastes space: the go tool binary size is 13MB
instead of 12MB, and the package size on amd64 is 48.7MB instead
of 45.3MB.

R=golang-dev, daniel.morsing, r, khr, rsc, iant
CC=golang-dev
https://golang.org/cl/13698043

(StdinPipe was taken care of by CL 13329043.)

Fixes #6008.

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/13606046

Because profiling signals can arrive at any time, we must
handle the case where a profiling signal arrives halfway
through a goroutine switch. Luckily, although there is much
to think through, very little needs to change.

Fixes #6000.
Fixes #6015.

R=golang-dev, dvyukov
CC=golang-dev
https://golang.org/cl/13421048