Removal of old zoneinfo files is a separate CL due to its size.

R=golang-dev, bradfitz, r
CC=golang-dev
https://golang.org/cl/5676100

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5677094

Most already had comments (yay); adjusted for consistency.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5676102

We should, after Go 1, make them work the same as
package xml, that is, make them appear in the outer
struct.  For now turn them off so that people do not
depend on the old behavior.

Fixing them is issue 3069.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5656102

The m->cret word holds the C return value when returning
across a stack split boundary.  It was not being cleared after
use, which means that the return value (if a C function)
or else the value of AX/R0 at the time of the last stack unsplit
was being kept alive longer than necessary.  Clear it.

I think the effect here should be very small, but worth fixing
anyway.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5677092

Fixes #3065

R=golang-dev, dsymonds, rsc
CC=golang-dev
https://golang.org/cl/5675094

R=ken2
CC=golang-dev
https://golang.org/cl/5674108

Delete Alloc, Free, Lookup, Semacquire, Semrelease

Fixes #2955.

R=golang-dev, r, bradfitz
CC=golang-dev
https://golang.org/cl/5675093

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5656103

I'm sure I wrote these before but they've disappeared.

R=golang-dev, bradfitz, r
CC=golang-dev
https://golang.org/cl/5673100

Very few of the compiler regression tests include a comment
saying waht they do. Many are obvious, some are anything but.
I've started with a-c in the top directory. More will follow once
we agree on the approach, correctness, and thoroughness here.
zerodivide.go sneaked in too.

R=rsc, r
CC=golang-dev
https://golang.org/cl/5656100

R=golang-dev, ken2
CC=golang-dev
https://golang.org/cl/5674098

Fixes #2964.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5656101

Fixes #3067.

R=golang-dev, rsc, rsc
CC=golang-dev
https://golang.org/cl/5656098

Generated by lib/time/update.bash.

R=bradfitz
CC=golang-dev
https://golang.org/cl/5676096

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5674104

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5674105

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5675092

Apply sed with:

1s,^// $G $D/$F.go && $L $F.$A && ./$A.out || echo.*,// run,
1s,^// $G $D/$F.go || echo.*,// compile,

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5656099

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5676094

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5677084

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5673080

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5673090

R=golang-dev, bradfitz, r, r
CC=golang-dev
https://golang.org/cl/5676090

R=golang-dev, adg, r
CC=golang-dev
https://golang.org/cl/5649068

Fixes #3053.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5656094

Because bug040.go was ignoring all error messages, the fact
that it got an error about fuction main was being ignored.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5675085

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5673089

R=r, bradfitz, r, adg
CC=golang-dev
https://golang.org/cl/5675076

When we build the encode engine for a recursive type, we
mustn't disregard the indirections or we can try to reuse an
engine at the wrong indirection level.

Fixes #3026.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5675087

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5671090

Fix by setting the element type if we discover it's zero while building.
We could have fixed this better with foresight by doing the id setting in a
different sequence, but doing that now would break binary compatibility.

Fixes #2995.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5675083

R=golang-dev, gri, r
CC=golang-dev
https://golang.org/cl/5676071

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5673087

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5676084

I am making a unilateral decision here. I could also settle for returning 0,
as long it's documented, but I argue that it's equivalent to an index
out of bounds.

Fixes #2892.

R=golang-dev, dsymonds, rsc
CC=golang-dev
https://golang.org/cl/5676079

R=golang-dev, r, gri
CC=golang-dev
https://golang.org/cl/5675081

Fixes #3048.

R=rsc
CC=golang-dev
https://golang.org/cl/5672081

Fixes #2989.

R=ken2
CC=golang-dev
https://golang.org/cl/5674091

Fixes #3061.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5656089