Merge branch 'maint'

* maint:
  options: try to report as much errors as possible
  warns: don't tell AM_PROG_MKDIR_P is going to be removed
  refactor: fix few "inverted boolean" usages
  options: better name for an internal function
  options: more consistency in use of return statuses to report errors
  options: tiny simplification in dealing with erroneous opts
  options: consistently use return statuses to report errors
  options: re-enable some sanity checks
  THANKS: update Eric Blake's e-mail address
  NEWS: typofix

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>

diff --cc NEWS
Simple merge

diff --cc bin/automake.in
Simple merge

diff --cc lib/Automake/Options.pm
index 3105b11eff577a651f05a509d422dc83555a232b,db5661cec695b8be773165eb4bdf5eeac89095f8..b0693bdb92763108fff9d59ee3bde1554e121ea9
--- 1/lib/Automake/Options.pm
--- 2/lib/Automake/Options.pm
+++ b/lib/Automake/Options.pm
@@@ -331,19 -337,22 +337,20 @@@ sub _process_option_list (\%@
          {
            error ($where, "support for lzma-compressed distribution " .
                           "archives has been removed");
+           $ret = 0;
          }
 -      # TODO: Make this a fatal error in Automake 2.0.
 +      # TODO: Remove this special check in Automake 3.0.
        elsif ($_ eq 'dist-shar')
          {
 -          msg ('obsolete', $where,
 -               "support for shar distribution archives is deprecated.\n" .
 -               "  It will be removed in Automake 2.0");
 +          error ($where, "support for shar distribution archives has " .
 +                         "been removed.");
          }
 -      # TODO: Make this a fatal error in Automake 2.0.
 +      # TODO: Remove this special check in Automake 3.0.
        elsif ($_ eq 'dist-tarZ')
          {
 -          msg ('obsolete', $where,
 -               "support for distribution archives compressed with " .
 -               "legacy program 'compress' is deprecated.\n" .
 -               "  It will be removed in Automake 2.0");
 +          error ($where, "support for distribution archives compressed " .
 +                         "with legacy program 'compress' has " .
 +                         "been removed.");
          }
        elsif (/^filename-length-max=(\d+)$/)
          {