[Automake-ng] [FYI] Merge branch 'master' into ng/master

[Stefano Lattarini]

commit 3cc7e84ead1ecbf1409604219a54093547b2d0a1
Merge: 112d08a 6dad21b
Author: Stefano Lattarini <address@hidden>
Date:   Sat May 5 11:12:27 2012 +0200

    Merge branch 'master' into ng/master

    * master: (27 commits)
      maintcheck: avoid a couple of spurious failures
      maintcheck: reduce code duplication, increase coverage
      maintcheck: avoid a couple of spurious failures
      tests: avoid spurious failure on missing Obj C/C++ compiler
      dist: don't bother putting README first in $(DIST_COMMON)
      news: document improvement in parallel-tests performance
      tests: fix spurious failure due to autom4te caching
      objc, objc++: test support for compilation flags
      objc, objc++: add stress test
      objc, objc++: test automatic dependency tracking
      objc: reorganize basic tests
      objc++, objc: add first semantic tests
      objc++: add first basic test
      news: fix typos
      aclocal: error out again on unrecognized arguments
      cosmetics: fix typo in aclocal m4 directory README
      silent rules: support for them is always active now
      parallel-tests: save few forks when possible
      cygnus: remove support for Cygnus-style trees
      cygnus: warn when it's used (flagged as 'obsolete' now)
      ...

    Extra non-trivial edits:

    * t/parallel-tests-unreadable.sh: Adjust to new error message for
    I/O errors.
    * t/silent6.sh: In Automake-NG, there is no 'portability-recursive'
    warning category anymore.  Adjust accordingly.
    * lib/am/check.am (am__create_global_log): Don't exit at the first
    I/O error, but report as much as possible of them.  If we don't do
    so, the test 't/parallel-tests-unreadable.sh' starts failing.

    Signed-off-by: Stefano Lattarini <address@hidden>