For the compile.el error regexps, perl's Test.pm can add a "fail #N" if
a given test line is run more than once, in a loop or subr.  The
`perl--Test2' could match that per below.  (Still no good on bzr, so
individual diffs.)

2011-03-29  Kevin Ryde  <user42@zip.com.au>

	* progmodes/compile.el (compilation-error-regexp-alist-alist):
	`perl-Test2' extend to match possible "fail #N" rep count.

2011-03-29  Kevin Ryde  <user42@zip.com.au>

	* compilation.txt (perl-Test2): New samples.