Re: [PATCH] lower cap on max_cmd_len to fix hppa2.0w-hp-hpux11.00

[Gary V . Vaughan]

On Tuesday 10 July 2001  1:05 am, Michael Elizabeth Chastain wrote:
> For my bribe, I will spend some time this weekend looking at something
> in the libtool TODO file.  Maybe I can figure out the "zsh echo"
> problem or something.
>
> MichaelC

I don't know if you have noticed, but the size of the libtool distribution 
grows exponentially with the size of libtool.m4.  This is because each demo 
directory has a copy of libtool.m4 as acinclude.m4, and another copy as 
aclocal.m4.  A really nice weekend project would be to write a dist-hook 
which removes all these copies of libtool.m4 (being careful to preserve the 
additional stuff added by aclocal) at `make dist' time, and add some magic to 
the `make check' rules (or perhaps to the configure script) to put the copies 
back together from the distributed libtool.m4.

A quick experiment shows how much space we waste with this duplication:

  $ ls -s libtool-1.4b.tar.gz
   1916 libtool-1.4b.tar.gz
  $ tar zxf libtool-1.4b.tar.gz
  $ rm -f libtool-1.4b/*demo/acinclude.m4
  $ rm -f libtool-1.4b/*demo/aclocal.m4
  $ tar chozf libtool-1.4b.tar.gz libtool-1.4b
  $ ls -s libtool-1.4b.tar.gz
   1436 libtool-1.4b.tar.gz

Almost half a meg!  I expect the overheads of adding a few lines of shell 
code to configure.ac/Makefile.am will add only a few hundred bytes back to 
these figures...

The rest of the difference in size between 1.4 and 1.4b tarballs is due to 
the switch to autoconf-2.50, which produces much larger configure scripts.  
And we now have 8 of them!!

  $ cd libtool-1.4
  $ ls -s configure */configure
   172 cdemo/configure   176 demo/configure      212 libltdl/configure
   180 configure         172 depdemo/configure   184 mdemo/configure
  $ cd ../libtool-1.4b
  $ ls -s configure */configure
   424 cdemo/configure   428 depdemo/configure   432 pdemo/configure
   436 configure         484 libltdl/configure   432 tagdemo/configure
   432 demo/configure    440 mdemo/configure

These guys each carry a fantastic amount of duplicated shell code (at least 
the entirety of the expanded libtool.m4 file).  A more advanced project might 
be to find and extract the largest common block to a single file, and then in 
the dist-hook replace that block in each configure script with a source 
command: `. $top_srcdir/libtool.ac' or something...

Just a quick hack to get a feel for how much this could shrink the tarball:

  $ cd libtool-1.4b
  $ rm -i */configure
  rm: remove `cdemo/configure'? y
  rm: remove `demo/configure'? y
  rm: remove `depdemo/configure'? y
  rm: remove `libltdl/configure'? y
  rm: remove `mdemo/configure'? n
  rm: remove `pdemo/configure'? n
  rm: remove `tagdemo/configure'? n
  $ cd ..
  $ tar chozf libtool-1.4b.tar.gz libtool-1.4b
  $ ls -s libtool-1.4*.tar.gz
   1072 libtool-1.4.tar.gz        1044 libtool-1.4b.tar.gz  

Cheers,
        Gary.
-- 
  ())_.  Gary V. Vaughan     gary@(oranda.demon.co.uk|gnu.org)
  ( '/   Research Scientist  http://www.oranda.demon.co.uk        ,_())____
  / )=   GNU Hacker          http://www.gnu.org/software/libtool   \'      `&
`(_~)_   Tech' Author        http://sources.redhat.com/autobook    =`---d__/