Actually it already worked since the spec only requires that
the one immediately preceding a for/switch/... be usable as
the target of a break or continue statement.

Added a test.
Also: allocate Function.lblocks on first use.

R=gri
CC=golang-dev
https://golang.org/cl/7365058

The original go-mode is plagued with odd behaviour, lack of
behaviour typical to modes in Emacs and bugs.

This change rewrites great parts of go-mode (basically only
keeping the gofmt and godoc functions).

Additionally it adds new features such as manipulating package
imports.

For more information please see
https://groups.google.com/group/golang-nuts/browse_frm/thread/3a9d6dae3369c0b5/1efe65e2f7afb190

Fixes #3618.
Fixes #4240.
Fixes #4322.
Fixes #4671.
Fixes #4726.

R=golang-dev, fullung, sameer, cw, arthur, proppy, adonovan, rsc, bradfitz
CC=golang-dev
https://golang.org/cl/7314113

And fix test. Pointer to unsafe.Pointer tests nothing important...
Also identify the incorrect type: go/types.Type is a Stringer.

Also fix a couple of incorrect format verbs found by new printf checker,
now that we can run it on more files.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7385051

The previous approach desugared the ast.SelectorExpr
to make implicit field selections explicit.  But:
1) it was clunky since it required allocating temporary
   syntax trees.
2) it was not thread-safe since it required poking
   types into the shared type map for the new ASTs.
3) the desugared syntax had no place to represent the
   package lexically enclosing each implicit field
   selection, so it was as if they all occurred in the
   same package as the explicit field selection.
   This meant unexported field names changed meaning.

This CL does what I should have done all along: just
generate the SSA instructions directly from the original
AST and the promoted field information.

Also:
- add logStack util for paired start/end log messages.
  Useful for debugging crashes.

R=gri
CC=golang-dev
https://golang.org/cl/7395052

Generated by addca (mostly, until codereview
blew up)

R=golang-dev
CC=golang-dev
https://golang.org/cl/7386054

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7370050

R=minux.ma, rsc, akumar, bradfitz
CC=golang-dev
https://golang.org/cl/7313070

Adjust the exit status string for Plan 9.

Upon allocating >100 file descriptors, Plan 9
raises a warning. Moreover, the Go runtime for
32-bit version of Plan 9 keeps /dev/bintime
open for its implementation of runtime.nanotime().
This change accounts for these things in
TestExtraFiles.

R=rsc, rminnich, ality, bradfitz
CC=golang-dev
https://golang.org/cl/7363056

Also, I synced the rc files with changes
that have been made to make.bash, etc.

R=seed, rminnich, r
CC=golang-dev
https://golang.org/cl/7389049

R=seed, rminnich, r, minux.ma
CC=golang-dev
https://golang.org/cl/7397059

Context.Alignof/Offsetsof/Sizeof now provide means
to customize the type checker for a given platform.

- provide Context.Offsetsof to specify the
  offsets of struct fields
- use the correct sizes for ints, uint, uintptrs
  in constant computations
- moved all size computations into separate file
  (sizes.go)
- fixed a bug with string constant slicing

R=adonovan, axwalk
CC=golang-dev
https://golang.org/cl/7363054

- imported objects don't have position information
- gc exported data contains non-exported objects at
  the top-level, guard against them
- better error message when dot-imports conflict
  with local declarations

R=adonovan, r
CC=golang-dev
https://golang.org/cl/7379052

R=adonovan, r
CC=golang-dev
https://golang.org/cl/7376055

pkg/go/doc: move BUG notes from Package.Bugs to the general Package.Notes field.
Removing .Bugs would break existing code so it's left in for now.

R=gri, gri, gary.burd, dsymonds, rsc, kevlar
CC=golang-dev
https://golang.org/cl/7341053

Fixes #4760.

R=golang-dev, minux.ma, bradfitz
CC=golang-dev
https://golang.org/cl/7312053

Separates the implementation of nanotime on 64-bit
version of Plan 9 from that on the 32-bit version.
The former uses a syscall.

R=rsc, rminnich, ality
CC=golang-dev
https://golang.org/cl/7379051

R=dr.volker.dobler
CC=golang-dev
https://golang.org/cl/7398049

Also restores the checking of _test.go files, which disappeared
as a result of the package-at-a-time change.
Fixes #4895.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7399051

Functions for representing network connections as files
and vice versa, on Plan 9.

Representing network connections as files is not so
straight-forward, because a network connection on Plan 9
is represented by a host of files rather than a single
file descriptor (as is the case on UNIX). We use the
type system to distinguish between listeners and
connections, returning the control file in the former
case and the data file in the latter case.

R=rsc, rminnich, ality, akumar, bradfitz
CC=golang-dev
https://golang.org/cl/7235068

Then mark them with a build tag so they're not compiled into the binary.
They are called test_*.go rather than *_test.go because they are not
for go test. Use make test to test the command.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/7377052

Fixes #4781.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7365056

Composite literals using the &T{} form were incorrectly
exported, leading to weird errors at import time.

Fixes #4879.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7395054

This avoids an allocation when closures are used
as "macros", in Walk idioms, or as argument to defer.

benchmark                old ns/op    new ns/op    delta
BenchmarkSearchWrappers       1171          354  -69.77%
BenchmarkCallClosure             3            3  -12.54%
BenchmarkCallClosure1          119            7  -93.95%
BenchmarkCallClosure2          183           74  -59.18%
BenchmarkCallClosure3          187           75  -59.57%
BenchmarkCallClosure4          187           76  -58.98%

Compared to Go 1:
benchmark                  old ns/op    new ns/op    delta
BenchmarkSearchWrappers         3208          354  -88.97%

Fixes #3520.

R=daniel.morsing, bradfitz, minux.ma, dave, rsc
CC=golang-dev
https://golang.org/cl/7397056

Fixes #4858.

R=golang-dev, bradfitz, r, rsc
CC=golang-dev
https://golang.org/cl/7387044

Fixes #4903.

R=golang-dev, daniel.morsing, dave, r
CC=golang-dev
https://golang.org/cl/7388056

Fixes #4810.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7401050

Fixes #3747.

Update #4912
This CL adds gotype into .5 object file.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7376054

Syscalls return `-1' on error and the representation is always
32-bits. The `$-1' literal in 64-bit assembly is always the
64-bit representation. So this change makes sure that we
always do a 32-bit comparison when checking for error.
Also makes sure that in the error case, we return a 64-bit
`-1' from runtime.seek.

Fixes the arithmetic for handling the error-string in
runtime.Syscall6.

R=golang-dev, rminnich, rsc, ality, minux.ma
CC=golang-dev
https://golang.org/cl/7399052

sigprocmask() is process-wide on darwin, so two concurrent
libcgo_sys_thread_start() can result in all signals permanently
blocked, which in particular blocks handling of nil derefs.
Fixes #4833.

R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/7324058

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7372048

Don't reference the non-portable syscall.Signal(0).

Maybe they'll pass too. Untested. plan9 bit from
Akshat Kumar.

R=golang-dev, akumar
CC=golang-dev
https://golang.org/cl/7370049

Now that the type information is in TYPE instructions
that are not rewritten by the optimization passes,
we don't have to try to preserve the type information
(no longer) attached to MOV instructions.

R=ken2
CC=golang-dev
https://golang.org/cl/7402054

This changeset adds a mostly-precise garbage collection of channels.
The garbage collection support code in the linker isn't recognizing
channel types yet.

Fixes issue http://stackoverflow.com/questions/14712586/memory-consumption-skyrocket

R=dvyukov, rsc, bradfitz
CC=dave, golang-dev, minux.ma, remyoudompheng
https://golang.org/cl/7307086

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7393059

Regenerate cmd/gc/builtin.c.
Fixes #4908.

R=rsc
CC=golang-dev
https://golang.org/cl/7383053

Now that vet does typechecking, it should use only pkg.gofiles, instead
of pkg.allgofiles. Ignored files should not be checked by vet, because
they wouldn't typecheck.

Fixes #4906.

R=rsc, r
CC=golang-dev
https://golang.org/cl/7401051

R=ken2
CC=golang-dev
https://golang.org/cl/7365057

The type information is (and for years has been) included
as an extra field in the address chunk of an instruction.
Unfortunately, suppose there is a string at a+24(FP) and
we have an instruction reading its length. It will say:

        MOVQ x+32(FP), AX

and the type of *that* argument is int (not slice), because
it is the length being read. This confuses the picture seen
by debuggers and now, worse, by the garbage collector.

Instead of attaching the type information to all uses,
emit an explicit list of TYPE instructions with the information.
The TYPE instructions are no-ops whose only role is to
provide an address to attach type information to.

For example, this function:

        func f(x, y, z int) (a, b string) {
                return
        }

now compiles into:

        --- prog list "f" ---
        0000 (/Users/rsc/x.go:3) TEXT    f+0(SB),$0-56
        0001 (/Users/rsc/x.go:3) LOCALS  ,
        0002 (/Users/rsc/x.go:3) TYPE    x+0(FP){int},$8
        0003 (/Users/rsc/x.go:3) TYPE    y+8(FP){int},$8
        0004 (/Users/rsc/x.go:3) TYPE    z+16(FP){int},$8
        0005 (/Users/rsc/x.go:3) TYPE    a+24(FP){string},$16
        0006 (/Users/rsc/x.go:3) TYPE    b+40(FP){string},$16
        0007 (/Users/rsc/x.go:3) MOVQ    $0,b+40(FP)
        0008 (/Users/rsc/x.go:3) MOVQ    $0,b+48(FP)
        0009 (/Users/rsc/x.go:3) MOVQ    $0,a+24(FP)
        0010 (/Users/rsc/x.go:3) MOVQ    $0,a+32(FP)
        0011 (/Users/rsc/x.go:4) RET     ,

The { } show the formerly hidden type information.
The { } syntax is used when printing from within the gc compiler.
It is not accepted by the assemblers.

The same type information is now included on global variables:

0055 (/Users/rsc/x.go:15) GLOBL   slice+0(SB){[]string},$24(AL*0)

This more accurate type information fixes a bug in the
garbage collector's precise heap collection.

The linker only cares about globals right now, but having the
local information should make things a little nicer for Carl
in the future.

Fixes #4907.

R=ken2
CC=golang-dev
https://golang.org/cl/7395056

See also CL 7383051 for details.

R=adonovan, bradfitz
CC=golang-dev
https://golang.org/cl/7378063

It's accessed without mutex protection
in a different goroutine from the one that
sets it.

Also make sure that Client.Call after Client.Close
will reliably return ErrShutdown, and that clients
see ErrShutdown rather than io.EOF when appropriate.

Suggestions welcome for a way to reliably test
the mutex issue.

R=r, iant
CC=golang-dev
https://golang.org/cl/7338045