cmd/vet: use go/printer to pretty-print expressions in printf messages
Fixes issue 4945.
Most examples in this issue now better, but #10 is incomplete and I'm not
certain how to reproduce it. It actually looks like a go/types problem, since
the type being reported is coming directly from that package.
Please reopen the issue if you disagree.

R=golang-dev, rsc
CC=golang-dev
https://codereview.appspot.com/7448046
runtime/cgo: fix arm build, re-enable test

Fixes issue 4961.

R=golang-dev, r, minux.ma
CC=golang-dev
https://codereview.appspot.com/7443048
runtime: special-case small byte appends.
Update issue 3679.

BenchmarkAppend1Byte            484          199  -58.88%
BenchmarkAppend4Bytes           829          286  -65.50%
BenchmarkAppend8Bytes           484          365  -24.59%
BenchmarkAppend16Bytes          484          498   +2.89%
BenchmarkAppend32Bytes          486          484   -0.41%

R=iant, dave, rsc
CC=golang-dev
https://codereview.appspot.com/7443047
runtime: special-case append([]byte, string) for small strings
Also make the crossover point an architecture-dependent constant,
although it's the same everywhere for now.

BenchmarkAppendStr1Byte            416          145  -65.14%
BenchmarkAppendStr4Bytes           743          217  -70.79%
BenchmarkAppendStr8Bytes           421          270  -35.87%
BenchmarkAppendStr16Bytes          415          403   -2.89%
BenchmarkAppendStr32Bytes          415          391   -5.78%

R=golang-dev, iant
CC=golang-dev
https://codereview.appspot.com/7459044
spec: fallthrough may not appear in last clause of a switch

Replacement for CL 7370053 which attempted to make fallthrough's
syntactically a part of switch statements. Because they may be
labeled, fixing that CL completely would require too much spec
surgery.

Fixes issue 4923.

R=r, iant, rsc, ken
CC=golang-dev
https://codereview.appspot.com/7416048
cmd/go: pass -intgosize to SWIG

swig >= 2.0.9 requires the size of int values to be passed via a command line flag. Should swig complain about the -intgosize not being supported, then alert the user to their outdated version of swig.

Fixes issue 4756.

R=golang-dev, minux.ma, iant
CC=golang-dev
https://codereview.appspot.com/7331048

Committer: Ian Lance Taylor <iant@golang.org>
go/types: fixed a few failure checks

More robustness in case of incorrect programs.

Fixes issue 4962.

R=dsymonds
CC=golang-dev
https://codereview.appspot.com/7429047
net: skip interface tests when required external command not found

Fixes issue 4952.

R=alex.brainman
CC=golang-dev
https://codereview.appspot.com/7445046
runtime: move TestGcSys into a separate process
Fixes issue 4904.
The problem was that when the test runs the heap had grown to ~100MB,
so GC allows it to grow to 200MB, and so the test fails.
Moving the test to a separate process makes it much more isolated and stable.

R=golang-dev, minux.ma
CC=golang-dev
https://codereview.appspot.com/7441046
runtime: deadlock tests now work with GOMAXPROCS>1
Fixes issue 4826.

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/7434046
exp: delete all packages except norm
They are moving to code.google.com/p/go.exp.
See also https://codereview.appspot.com/7463043

R=golang-dev, minux.ma
CC=golang-dev
https://codereview.appspot.com/7456047
misc/dashboard/app: make the builders test go.talks and go.exp

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/7419048
old/netchan: delete as part of move to go.exp/old/netchan

R=golang-dev, minux.ma
CC=golang-dev
https://codereview.appspot.com/7450050
doc/go1.1.html: document the moving of exp/... and old/....

R=golang-dev, minux.ma
CC=golang-dev
https://codereview.appspot.com/7445050
runtime: benchmark for appending N bytes should not append N² bytes.

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/7420051