Subject: bug#27781: LIBOBJS should depend on LIBOBJDIR

From: Mathieu Lirzin <[email-masked]>
Date: Tue, 22 Aug 2017 00:40:32 +0200

Michael Haubenwallner <[email-masked]> writes:

> In this case let me come up with attached patch for now
> (without deeper knowledge of automake internals though).

I have tested this patch, and confirm that it fixes the bug.  However I
have on question regarding the added code.

> From c3d51adb53400fc8bf65c0e003d810b2e7166d0d Mon Sep 17 00:00:00 2001
> From: Michael Haubenwallner <[email-masked]>
> Date: Wed, 16 Aug 2017 18:16:12 +0200
> Subject: [PATCH] automake: Depend on LIBOBJDIR for LIBOBJS.
>
> This change fixes automake bug#27781.
>
> * bin/automake.in: Add Makefile dependency on LIBOBJDIR/dirstamp for
> each LIBOBJS/ALLOCA variable used.
> ---
>  bin/automake.in | 11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/bin/automake.in b/bin/automake.in
> index 9c4cb86..b82e8c5 100644
> --- a/bin/automake.in
> +++ b/bin/automake.in
> @@ -2153,10 +2153,19 @@ sub handle_LIBOBJS_or_ALLOCA
>        $dir = backname ($relative_dir) . "/$dir"
>          if $relative_dir ne '.';
>        define_variable ('LIBOBJDIR', "$dir", INTERNAL);
> +      my $dirstamp = '';
> +      # Abusing $clean_files{"$(VAR)"} as indicator for whether
> +      # we have added the "$(VAR): $dirstamp" dependency already.

I am not sure to understand what this comment really means.  Can you
explain it in other words?
        
> +      $dirstamp = require_build_directory ($dir)
> +	if ! defined $clean_files{"\$($var)"};
>        $clean_files{"\$($var)"} = MOSTLY_CLEAN;
> +      $output_rules .= "\$($var): $dirstamp\n" if ($dirstamp);
>        # If LTLIBOBJS is used, we must also clear LIBOBJS (which might
>        # be created by libtool as a side-effect of creating LTLIBOBJS).
> -      $clean_files{"\$($var)"} = MOSTLY_CLEAN if $var =~ s/^LT//;
> +      if ($var =~ s/^LT//) {
> +	$clean_files{"\$($var)"} = MOSTLY_CLEAN;
> +	$output_rules .= "\$($var): $dirstamp\n" if ($dirstamp);
> +      }
>      }
>  
>    return $dir;

Thank you.

-- 
Mathieu Lirzin
GPG: F2A3 8D7E EB2B 6640 5761  070D 0ADE E100 9460 4D37