Two things to stop `make distcheck' from trying to rebuild

distributed files (m4/ltversion.m4 and config/ltmain.in) in the
readonly source tree:

* Makefile.am (stamp-vcl): Keep only one copy of stamp-vcl; in
$(top_srcdir), so that an up-to-date version is rolled into the
dist tarball even from a VPATH build.
($(top_srcdir)/config/ltmain.sh): Don't depend on Makefile,
otherwise ltmain.sh needs to be rebuilt after every config.status
run, and then configure needs to be rebuilt, and it all goes
horribly wrong :-/  Unfortunately, we can't depend on Makefile.am
either, because that is a circular dependency.  The downside of
this change is that it is now possible to edit Makefile.am to
change the way ltmain.sh is generated, and the dependency
information can't tell that ltmain.sh needs regenerating.

diff --git a/ChangeLog b/ChangeLog
index 39b87a28a5744bf9b9823f83f65031451fcf1f8e..df264d03bbfd4ac933e8f8c0e58fe832d2f1c654 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,21 @@
+2004-08-27  Gary V. Vaughan  <gary@gnu.org>
+
+       Two things to stop `make distcheck' from trying to rebuild
+       distributed files (m4/ltversion.m4 and config/ltmain.in) in the
+       readonly source tree:
+
+       * Makefile.am (stamp-vcl): Keep only one copy of stamp-vcl; in
+       $(top_srcdir), so that an up-to-date version is rolled into the
+       dist tarball even from a VPATH build.
+       ($(top_srcdir)/config/ltmain.sh): Don't depend on Makefile,
+       otherwise ltmain.sh needs to be rebuilt after every config.status
+       run, and then configure needs to be rebuilt, and it all goes
+       horribly wrong :-/  Unfortunately, we can't depend on Makefile.am
+       either, because that is a circular dependency.  The downside of
+       this change is that it is now possible to edit Makefile.am to
+       change the way ltmain.sh is generated, and the dependency
+       information can't tell that ltmain.sh needs regenerating.
+
 2004-08-27  Gary V. Vaughan  <gary@gnu.org>
 
        * doc/libtool.texi (Cheap tricks): Escape the `@' for texinfo.

diff --git a/Makefile.am b/Makefile.am
index 47d40ce6f6eb1558020cfb1bbcc4e324a5663593..cea3b0d85cc1db73d9e1cfd4209a09aadf0ef1b4 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -59,18 +59,18 @@ dist_pkgdata_DATA = config/config.guess config/config.sub config/ltmain.sh
 aclocal_DATA = m4/argz.m4 m4/libtool.m4 m4/ltdl.m4 \
        m4/ltoptions.m4 m4/ltsugar.m4 m4/ltversion.m4
 
-## If mkstamp does not match $(srcdir)/stamp-vcl, we still put the new one
-## in the current dir, incase $(srcdir) is not writable.  The dir selection
-## at the top of this rule takes care of prefering the right one on
-## subsequent runs.
+## We know that $(top_srcdir)/ChangeLog has been edited if stamp-vcl
+## needs updating, so we assume we have write access to $(top_srcdir).
+## If we try to maintain ./stamp-vcl to avoid writing to a possibly
+## read-only $(top_srcdir), then when the two stamp-vcls differ, distcheck
+## will try to update the one in the read-only source tree it makes.
 MKSTAMP = $(SHELL) $(top_srcdir)/config/mkstamp
-stamp-vcl: vcl-tmp ChangeLog
+$(top_srcdir)/stamp-vcl: vcl-tmp ChangeLog
 vcl-tmp:
-       @dir=.; test -f $$dir/stamp-vcl || dir=$(srcdir); \
-       set -- `$(MKSTAMP) < $(top_srcdir)/ChangeLog`; \
+       @set -- `$(MKSTAMP) < $(top_srcdir)/ChangeLog`; \
        echo "$$1" > vcl.tmp; \
-       cmp -s vcl.tmp $$dir/stamp-vcl \
-         || (echo "Updating stamp-vcl"; cp vcl.tmp ./stamp-vcl)
+       cmp -s vcl.tmp $(top_srcdir)/stamp-vcl \
+         || (echo "Updating stamp-vcl"; cp vcl.tmp $(top_srcdir)/stamp-vcl)
        -@rm -f vcl.tmp
 
 # We build ltversion.m4 here, instead of from config.status,
@@ -94,8 +94,14 @@ $(top_srcdir)/m4/ltversion.m4: m4/ltversion.in configure.ac stamp-vcl
        mv -f m4/ltversion.tmp m4/ltversion.m4
 
 ## And for similar reasons, ltmain.sh can't be built from config.status.
+## WARNING: If you edit this rule to change the contents of ltmain.sh,
+##          you must `touch $(top_srcdir)/config/ltmain.in' from the
+##          shell if you need ltmain.sh to be regenerated.  Ideally, we
+##          should make this rule depend on Makefile but that will break
+##          distcheck (at least) by rebuilding ltmain.sh in the source
+##          tree whenever config.status regenerates the Makefile.
 EXTRA_DIST += config/ltmain.sh
-$(top_srcdir)/config/ltmain.sh: config/ltmain.in configure.ac stamp-vcl Makefile
+$(top_srcdir)/config/ltmain.sh: config/ltmain.in configure.ac stamp-vcl
        $(timestamp); \
        cd $(top_srcdir); \
        rm -f config/ltmain.tmp; \