Also fixes color gradient being calculated against the wrong maximum.

R=adonovan
CC=golang-dev
https://golang.org/cl/12968043

The goal is to stop only those programs that would keep
going and run the machine out of memory, but before they do that.
1 GB on 64-bit, 250 MB on 32-bit.
That seems implausibly large, and it can be adjusted.

Fixes #2556.
Fixes #4494.
Fixes #5173.

R=khr, r, dvyukov
CC=golang-dev
https://golang.org/cl/12541052

Use more compressed image to reduce source clutter.

Fixes #5983.

R=nigeltao, adg
CC=golang-dev
https://golang.org/cl/12513044

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/13024045

Rows.Close.

Previously, callers that followed the example code (but not call
rows.Close after "for rows.Next() { ... }") could leak statements if
the driver returned an error other than io.EOF.

R=bradfitz, alex.brainman
CC=golang-dev, rsc
https://golang.org/cl/12677050

TBR=dvyukov
CC=golang-dev
https://golang.org/cl/12791044

Also start of some test helper unification, long overdue.
I refrained from cleaning up the rest in this CL.

Fixes #6157

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/13030043

It's nearly useless and for plain 'go doc', 'godoc .' works fine.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/13004044

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12931044

It's next to useless and confusing as well. Let's make godoc better instead.

Fixes #4849.

R=golang-dev, dsymonds, adg, rogpeppe, rsc
CC=golang-dev
https://golang.org/cl/12974043

One was tiny. One was gigantic. Now one is gone and one is giganticer.

No code changes.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/13025043

See golang.org/s/go12nil.

This CL is about getting all the right checks inserted.
A followup CL will add an optimization pass to
remove redundant checks.

R=ken2
CC=golang-dev
https://golang.org/cl/12970043

See golang.org/s/go12nil for the extended version.

R=golang-dev, r, adonovan
CC=golang-dev
https://golang.org/cl/12964043

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12858044

R=golang-dev, jsing
CC=golang-dev
https://golang.org/cl/12876044

Fixes #5199.

Benchmark results on freebsd/amd64 (virtual machine):

benchmark                             old ns/op    new ns/op    delta
BenchmarkTCP4OneShot-2                   184566       187164   +1.41%
BenchmarkTCP4OneShotTimeout-2            215558       187722  -12.91%
BenchmarkTCP4Persistent-2                 59686        41294  -30.81%
BenchmarkTCP4PersistentTimeout-2          60692        39974  -34.14%
BenchmarkTCP6OneShot-2                   226595       223688   -1.28%
BenchmarkTCP6OneShotTimeout-2            253144       225161  -11.05%
BenchmarkTCP6Persistent-2                 69157        55605  -19.60%
BenchmarkTCP6PersistentTimeout-2          70426        53805  -23.60%
BenchmarkTCP4ConcurrentReadWrite-2        53878        56087   +4.10%
BenchmarkTCP6ConcurrentReadWrite-2        66538        68190   +2.48%

benchmark                            old allocs   new allocs    delta
BenchmarkTCP4OneShot-2                       39           36   -7.69%
BenchmarkTCP4OneShotTimeout-2                42           36  -14.29%
BenchmarkTCP4Persistent-2                     1            0  -100.00%
BenchmarkTCP4PersistentTimeout-2              1            0  -100.00%
BenchmarkTCP6OneShot-2                       41           36  -12.20%
BenchmarkTCP6OneShotTimeout-2                43           36  -16.28%
BenchmarkTCP6Persistent-2                     1            0  -100.00%
BenchmarkTCP6PersistentTimeout-2              1            0  -100.00%
BenchmarkTCP4ConcurrentReadWrite-2            0            0     n/a%
BenchmarkTCP6ConcurrentReadWrite-2            0            0     n/a%

benchmark                             old bytes    new bytes    delta
BenchmarkTCP4OneShot-2                     3084         2544  -17.51%
BenchmarkTCP4OneShotTimeout-2              3129         2519  -19.50%
BenchmarkTCP4Persistent-2                    30            0  -100.00%
BenchmarkTCP4PersistentTimeout-2             31            0  -100.00%
BenchmarkTCP6OneShot-2                     3297         2660  -19.32%
BenchmarkTCP6OneShotTimeout-2              3306         2655  -19.69%
BenchmarkTCP6Persistent-2                    31            0  -100.00%
BenchmarkTCP6PersistentTimeout-2             29            0  -100.00%
BenchmarkTCP4ConcurrentReadWrite-2            2            0  -100.00%
BenchmarkTCP6ConcurrentReadWrite-2            7            0  -100.00%

R=dvyukov, minux.ma, dave, bradfitz, alex.brainman
CC=golang-dev
https://golang.org/cl/8264043

runtime.gcwaiting checks are not needed anymore

R=golang-dev, khr
CC=golang-dev
https://golang.org/cl/12934043

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/12986043

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12960043

This CL rearranges the call order for raw networking primitives like
the following;

- For dialers that open active connections, pollDesc.Init will be
  called before syscall.Connect.

- For stream listeners that open passive stream connections,
  pollDesc.Init will be called just after syscall.Listen.

- For datagram listeners that open datagram connections,
  pollDesc.Init will be called just after syscall.Bind.

This is in preparation for runtime-integrated network pollster for BSD
variants.

Update #5199

R=golang-dev, alex.brainman
CC=golang-dev
https://golang.org/cl/12730043

I tried to make it absolutely correct but there are too many
conflicting definitions for the official list of time zones.
Since when we're parsing we know when to expect
a time zone and we know what they look like if not exactly
what the definitive set is, we compromise. We accept any
three-character sequence of upper case letters, possibly
followed by a capital T (all four-letter zones end in T).

There is one crazy special case (ChST) and the possibility
of a signed hour offset for GMT.

Fixes #3790
I hope forever, but I doubt that very much.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/12969043

Took 76 seconds or so before. By avoiding flate and crc32 on
4GB of data, it's now only 12 seconds.  Still a slow test, but
not painful to run anymore when you forget -short.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/12950043

R=golang-dev, kevlar, rsc, adg, r
CC=golang-dev
https://golang.org/cl/12962043

Fixes #3622

R=golang-dev, alex.brainman
CC=golang-dev
https://golang.org/cl/12971043

One sentence says they're ignored, another says they take part.
Fix the first.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12741046

whatever "end-to-end" means here

R=golang-dev, dvyukov
CC=golang-dev
https://golang.org/cl/12898044

Was checking for nil map; must check for empty map instead.

Fixes #6065

Before:

go test -cover
# testmain
/var/folders/00/013l0000h01000cxqpysvccm0004fc/T/go-build233480051/_/Users/r/issue/_test/_testmain.go:11: imported and not used: "_/Users/r/issue"
FAIL	_/Users/r/issue [build failed]

Now:

go test -cover
testing: warning: no tests to run
PASS
coverage: 0.0% of statements
ok  	_/Users/r/issue	0.021s

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12916043

Update #3790
Handle time zones like GMT-8.
The more general time zone-matching problem is not yet resolved.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12922043

Fixes #6042.

R=adg
CC=golang-dev
https://golang.org/cl/12923043

R=golang-dev, adonovan, bradfitz
CC=golang-dev
https://golang.org/cl/12721043

Remove custom support for time.Time.
No new tests: the tests for the time.Time special case
now test the general case.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12751045

The baseline architecture had been left to the GCC configured
default which can be more accomodating than the rest of the Go
toolchain.  This prevented instructions used by the 5g compiler,
like BLX, from being used in GCC compiled assembler code.

R=golang-dev, dave, rsc, elias.naur, cshapiro
CC=golang-dev
https://golang.org/cl/12954043

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12957044

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/12953043

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12884044

        CL 12741044 added an extra iself condition to an if statement that already contained it. Remove it.

R=rsc
CC=golang-dev
https://golang.org/cl/12949043

It doughtily misses all possible corner cases.
In particular on machines with <1GHz processors,
SetBlockProfileRate(1) disables profiling.
Fixes #6114.

R=golang-dev, bradfitz, rsc
CC=golang-dev
https://golang.org/cl/12936043

Also does less buffer allocation in case of TCP fallback.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12925043

R=golang-dev, dvyukov, dave
CC=golang-dev
https://golang.org/cl/12766044

Will submit once I can fill in the CL XXX number.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/12912044