dist: obsolete support for lzma (superseded by xz and lzip)

The lzma utilities are today superseded by the xz utilities; in
fact, the official site at <http://tukaani.org/lzma/> reads:

  ``LZMA Utils are legacy data compression software with high
    compression ratio.  LZMA Utils are no longer developed, ...
    Users of LZMA Utils should move to XZ Utils.''

and the existing automake manual (as of 1.11.2) already says:

  ``dist-xz
    Generate an 'xz' tar archive of the distribution. xz archives
    are frequently smaller than bzip2-compressed archives. The 'xz'
    format will soon (early 2009) displace the 'lzma' format''

Also, the `dist-lzma' target still suffers of never-solved bugs,
due to the too-high compression ratio its uses by default, which
might cause an unacceptable memory consumption when one tries to
compress or, worse, decompress the created tarballs; see also:

  <http://lists.gnu.org/archive/html/automake/2011-12/msg00025.html>
  <http://debbugs.gnu.org/cgi/bugreport.cgi?bug=9658>

* NEWS: Update.
* doc/automake.texi (Dist, Options): State that `dist-lzma' will
go away in the next major automake version.
* lib/Automake/Options.pm (_process_option_list): Deprecate
`dist-lzma'.
* tests/lzma.test: Update.

1 files changed, 3 insertions, 3 deletions

diff --git a/doc/automake.texi b/doc/automake.texi
index e155fd167..976c2f81b 100644
--- a/doc/automake.texi
+++ b/doc/automake.texi
@@ -8667,10 +8667,10 @@ Generate a gzip tar archive of the distribution.
 @trindex dist-gzip
 
 @item @code{dist-lzma}
-Generate an @samp{lzma} tar archive of the distribution.  @command{lzma}
-archives are frequently smaller than @command{bzip2}-compressed archives.
+Generate an @samp{lzma} tar archive of the distribution.
 The @samp{lzma} format is obsolete, you should use the @samp{xz} format
-instead.
+instead. @emph{Support for @samp{lzma}-compressed archives will be
+removed in the next major Automake release.}
 @trindex dist-lzma
 
 @item @code{dist-shar}