Re: subdir-objects & depcomp trouble

[Stepan Kasal]

Hello again,

in a private mail, Patrick pointed out some problems in my answer:

On Mon, Oct 03, 2005 at 02:15:29PM +0200, Stepan Kasal wrote:
> You should use a relative path, ie. in lib/Makefile.am you should use:
> 
> libmylib_la_SOURCES = ../src/myfile.cc

I should have said _literal_ relative path.  The reason is that the shell
code for the "depfile commands" which comes from depout.m4 and get's executed
near the end of ./configure, does't interpret '$(top_srcdir)'.

This means that my suggestion:

> libmylib_la_SOURCES = $(top_builddir)/src/myfile.cc

wouldn't work with current Automake.  It can be fixed, though.
(There are two ways to fix it: top_builddir can be interpreted in depout.m4,
or it can be replaced by automake; a patch implementing the latter is
attached below--but I don't know whether this is The Right Way.)

But I still believe that I was right that

> > libmylib_la_SOURCES = $(top_srcdir)/src/myfile.cc

is wrong.  I think Automake should issue an error if SOURCES contains
$(srcdir) or $(top_srcdir).

But I don't know how to implement it.  Alexandre, help us, please!

Have a nice day,
        Stepan

2005-10-03  Stepan Kasal  <address@hidden>

        * automake.in (handle_languages): Expand $(top_builddir) in the
          path to the dependency file.

Index: automake.in
===================================================================
RCS file: /cvsroot/automake/automake/automake.in,v
retrieving revision 1.1612
diff -u -r1.1612 automake.in
--- automake.in 13 Sep 2005 20:16:33 -0000      1.1612
+++ automake.in 3 Oct 2005 18:57:47 -0000
@@ -1307,6 +1307,9 @@
            my $output_flag = $lang->output_flag || '-o';
 
            my $depbase = dirname ($obj);
+           # Expand $(top_builddir), because _AM_OUTPUT_DEPENDENCY_COMMANDS
+           # doesn't do it.
+           $depbase =~ s/\$\(top_builddir\)/backname($relative_dir)/e;
            $depbase = ''
                if $depbase eq '.';
            $depbase .= '/'