Fixes #1756.

R=ken2
CC=golang-dev
https://golang.org/cl/4810057

Fixes #2020.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/4814056

Fixes #1774.
Fixes #2095.
Fixes #2097.

R=ken2
CC=golang-dev
https://golang.org/cl/4826046

Fixes #1662.

R=ken2
CC=golang-dev
https://golang.org/cl/4828045

Fixes #1192.

R=ken2
CC=golang-dev
https://golang.org/cl/4794062

Fixes #591.

R=ken2
CC=golang-dev
https://golang.org/cl/4803054

R=nigeltao
CC=golang-dev
https://golang.org/cl/4825050

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4802061

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4809052

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4819048

R=bradfitz, rsc
CC=golang-dev
https://golang.org/cl/4815062

Fixes #1856.

R=ken2
CC=golang-dev
https://golang.org/cl/4810054

Fixes #1393.

R=ken2
CC=golang-dev
https://golang.org/cl/4811054

Fixes #1600.

R=ken2
CC=golang-dev
https://golang.org/cl/4819045

Fixes #2078.

R=rsc
CC=golang-dev
https://golang.org/cl/4800052

Undo CL 4254056 now that enough time has elapsed
that people with old trees have all built and removed
those files (which are no longer generated in that location).

Fixes #1581.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/4802059

R=rsc
CC=golang-dev
https://golang.org/cl/4809044

We must keep memory used by syscall.WSARecvFrom away from
garbage collector until after overlapped call is completed.

Fixes #2094.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4817050

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4801053

ld/data.c:
. Format specifier with corresponding cast to cater for all
  architectures (llux and vlong).

ld/ldelf.c:
ld/ldmacho.c:
. Missing "pn" argument in diag() calls.

ld/ldpe.c:
. Dropped "sym->sectnum" in diag() call.
. Typo in a comment.

ld/lib.h:
. Added varargck pragma for "O".

R=rsc
CC=golang-dev
https://golang.org/cl/4749042

. By defining getcallerpc(x) as __builtin_return_address(0)
  here, it becomes possible to use the Plan 9 compatible form
  when compiling using GCC.  The alternative is to add conditional
  compilation based on the compiler identity in "cmd/8g/gsubr.c"
  to distinguish between the two cases.

R=golang-dev
CC=golang-dev, rsc
https://golang.org/cl/4800048

. Replaced Posix #includes with u.h and libc.h.
. Replaced fprintf(stderr,...); exit(1); with sysfatal() calls.

R=golang-dev
CC=golang-dev, rsc
https://golang.org/cl/4823047

R=rsc
CC=golang-dev
https://golang.org/cl/4742042

some object files don't has file name symbol.

R=golang-dev, lucio.dere, rsc
CC=golang-dev
https://golang.org/cl/4814051

R=golang-dev
CC=alex.brainman, golang-dev
https://golang.org/cl/4816049

Fixes #2102.

R=fullung, rsc
CC=golang-dev
https://golang.org/cl/4825043

R=golang-dev, vcc.163, rsc
CC=golang-dev
https://golang.org/cl/4826042

When rnd is called with a second argument of 1, it simply
returns the first argument anyway.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4820045

Still need to write tests for new syntax
and fix bugs that the tests find, but this
is a good check point.

All tests pass.

Compared against existing regexp:

benchmark                                old ns/op    new ns/op    delta
regexp.BenchmarkLiteral                       1869          620  -66.83%
regexp.BenchmarkNotLiteral                    9489         7823  -17.56%
regexp.BenchmarkMatchClass                   10372         8386  -19.15%
regexp.BenchmarkMatchClass_InRange           10800         7750  -28.24%
regexp.BenchmarkReplaceAll                   13492         8519  -36.86%
regexp.BenchmarkAnchoredLiteralShortNonMatch   747          339  -54.62%
regexp.BenchmarkAnchoredLiteralLongNonMatch    599          335  -44.07%
regexp.BenchmarkAnchoredShortMatch            2137          917  -57.09%
regexp.BenchmarkAnchoredLongMatch             2029          917  -54.81%

R=r, r
CC=golang-dev, sam.thorogood
https://golang.org/cl/4820046

goinstall: report every newly installed package to the dashboard

This makes "goinstall -a" work on systems with GOROOTs that are
not user-writable, as is the case with Debian's Go packages.

This also makes goinstall.log the canonical list of installed
packages, in that only packages new to goinstall.log are reported to
the dashboard.

A side-effect is that writing to goinstall.log is now mandatory.
(A bug in the original implementation meant this was the case, anyway.)

The principal benefit of this change is that multiple packages from the
same repository can now be reported to the dashboard.  It is also less
likely for a user to report multiple installations of the same package
to the dashboard (they would need to remove the package from
goinstall.log first).

R=rsc, n13m3y3r
CC=golang-dev
https://golang.org/cl/4786041

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4811050

Previously comparisons with NaN led to contradictory results if it was
compared to anything not NaN, since Less always returned false, thus
breaking monotonicity of ordering.
This fix makes NaN less than anything else and adds NaN and (+-)Inf to
testcases.

Fixes #2092.

R=golang-dev, r, rsc, r
CC=golang-dev
https://golang.org/cl/4805051

R=golang-dev, r, r, dsymonds, rsc
CC=golang-dev
https://golang.org/cl/4813043

Replace cas with xadd in scheduler.
Suggested by Dmitriy in last code review.
Verified with Promela model.

When there's actual contention for the atomic word,
this avoids the looping that compare-and-swap requires.

benchmark                            old ns/op    new ns/op    delta
runtime_test.BenchmarkSyscall               32           26  -17.08%
runtime_test.BenchmarkSyscall-2            155           59  -61.81%
runtime_test.BenchmarkSyscall-3            112           52  -52.95%
runtime_test.BenchmarkSyscall-4             94           48  -48.57%
runtime_test.BenchmarkSyscallWork          871          872   +0.11%
runtime_test.BenchmarkSyscallWork-2        481          477   -0.83%
runtime_test.BenchmarkSyscallWork-3        338          335   -0.89%
runtime_test.BenchmarkSyscallWork-4        263          256   -2.66%

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/4800047

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4794056

This is the last piece (I hope) of the set creation code.
These helpers create sets from files containing individual
template definitions, free of {{define}} clauses. This
design is helpful if the templates live one per file,
undecorated.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/4801052

R=r, iant
CC=golang-dev
https://golang.org/cl/4809050

Fixes a problem where Readdir would always return
empty directories (Readdir is only called by godoc
if the usual directory handler is commented out
in godoc.go, and if a zip file system is provided;
thus, this bug never manifested itself in godoc).

Also:
- better choice of variable/field names
- simplified error handling a bit
- better comments

R=bradfitz
CC=golang-dev
https://golang.org/cl/4813047

This surprisingly takes 30 seconds on my fast machine
so disabling by default. Need to optimize the Writer
at some point.

R=golang-dev, r, r
CC=golang-dev
https://golang.org/cl/4815048

This makes the full file paths recorded by 6g
prefer $PWD over the actual directory name
(relevant when $PWD gets to the current directory
via symlinks).  It's what everyone else does, and
what people expect.

R=iant, r, mattn.jp
CC=golang-dev
https://golang.org/cl/4824041