[PATCH] dist-xz: don't hard-code -9: honor setting of XZ_OPT

[Jim Meyering]

* lib/am/distdir.am (dist-xz): Do not hard-code xz's -9: that
made it impossible to override.  Instead, use its XZ_OPT envvar,
defaulting to -9 if not defined.  Thus no change in behavior
when XZ_OPT is not set, and now, this rule honors the setting
of that envvar when it is set.  Suggested by Lasse Collin.
---

Lasse Collin raised this issue and suggested the fix.
This is especially useful when you run "make dist" or "make distcheck"
and just want it to complete quickly -- i.e., you don't require maximum
compression because you're not about to distribute the resulting tarball,
so the extra cycles to shave off 5-10% would be wasted.  Personally,
I will make the default for my projects be -7 or so, while for release,
I automatically use -9ev already, by specifying XZ_OPT=-9ev in the rule
that invokes "make dist".

Let me know if you'd like a NEWS entry, or any other change.

 lib/am/distdir.am |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/lib/am/distdir.am b/lib/am/distdir.am
index a11d3a4..0cd07e0 100644
--- a/lib/am/distdir.am
+++ b/lib/am/distdir.am
@@ -363,7 +363,8 @@ dist-lzma: distdir
 ?XZ?DIST_ARCHIVES += $(distdir).tar.xz
 .PHONY: dist-xz
 dist-xz: distdir
-       tardir=$(distdir) && $(am__tar) | xz -9 -c >$(distdir).tar.xz
+       tardir=$(distdir) && $(am__tar) \
+         | XZ_OPT=$${XZ_OPT--9} xz -c >$(distdir).tar.xz
        $(am__post_remove_distdir)

 ?COMPRESS?DIST_ARCHIVES += $(distdir).tar.Z
--
1.7.3.1.45.g9855b