cmd/vet: check argument types in printf formats
Fixes issue 4404.

R=gri, rsc
CC=golang-dev
https://codereview.appspot.com/7378061
syscall: add if_announce support for freebsd

Update issue 4866.

R=golang-dev, dave
CC=golang-dev
https://codereview.appspot.com/7398047
syscall: add if_announce support for netbsd

Update issue 4866.

R=golang-dev, bradfitz, dave
CC=golang-dev
https://codereview.appspot.com/7382052
syscall: add if_announce support for openbsd

Update issue 4866.

R=golang-dev
CC=golang-dev
https://codereview.appspot.com/7382053
syscall: add network interface announce support on BSD variants

This CL allows to receive network interface arrival and depature
notifications through routing sockets on BSD variants. So far
Darwin doesn't support this feature.

Also does small simplification.

Update issue 4866.

R=golang-dev, lucio.dere, dave
CC=golang-dev
https://codereview.appspot.com/7365055
cmd/dist: avoid using %ebx on i386.
Or gcc (-fPIC) will complain:
cmd/dist/unix.c: In function ‘cansse2’
cmd/dist/unix.c:774: error: can't find a register in class ‘BREG’ while reloading ‘asm’
cmd/dist/unix.c:774: error: ‘asm’ operand has impossible constraints

This affects bootstrapping on native Darwin/386 where all code is
compiled with -fPIC.

R=golang-dev, iant
CC=golang-dev
https://codereview.appspot.com/7394047
runtime: remove PROT_EXEC from mmap calls.
Executable heap is gone on Unix!

R=golang-dev, dave, bradfitz
CC=golang-dev
https://codereview.appspot.com/7405045
crypto/rsa: fix infinite loop in GenerateMultiPrimeKey for large nprimes

The heuristics for BitLen of a product of randomly generated primes
are wrong, and the generated candidates never match the required
size for nprimes > 10. This corner case is not expected to be used in
practice.

R=agl
CC=golang-dev
https://codereview.appspot.com/7397052