[racket-dev] Parallel Build of Collects

I've run a nightly build, the problems are:

* [1] happened on all builds (text below).

* Uses 16 processes on windows (already solved in Matthew's recent push).

* Used the parallel build on windows when the setup line uses "-Dl
  compiler" to only make the compiler available.  (Possibly a feature,
  but it took a long time to run, likely because of the previous
  problem.)

* On this windows build (of the compiler collection, and also in the
  full setup later), there were many problems like:
    raco setup: ERROR: compiler compiler.rkt:
    rename-file-or-directory: cannot rename file or directory:
    f:\racket\collects\compiler\compiled\tmp1278373426620656247 to:
    f:\racket\collects\compiler\compiled\compiler_rkt.dep (Access is
    denied.; errno=5)
  This is some race condition that will likely be hidden on the next
  build (when it will use a single process), so it'll be good to use
  some multi-core windows machine to find the problem.


--[1]--------------------------------------------------------------------------
raco setup: build-output: parser-tools yacc-to-scheme.rkt
STDOUT:
Warning: lexer at #<syntax:/var/tmp/racket/collects/parser-tools/yacc-to-scheme.rkt:10:4 (lexer ((:* (:~ #\" #\\)) (ap...> can accept the empty string.
Warning: lexer at #<syntax:/var/tmp/racket/collects/parser-tools/yacc-to-scheme.rkt:17:4 (lexer ((:* (:~ #\' #\\)) (ap...> can accept the empty string.
=====
STDERR:
=====
-------------------------------------------------------------------------------

-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!