rewrite lib/g77.exp

[Alexandre Oliva]

On Nov 17, 2001, "Kaveh R. Ghazi" <ghazi@caip.rutgers.edu> wrote:

>> From: Alexandre Oliva <aoliva@redhat.com>

>> I recall a number of dynamic loaders will disregard LD_LIBRARY_PATH
>> when looking for dependencies of shared libraries.  This is one of the
>> reasons why I recommend using libtool for libgcc: then libtool will
>> know how to arrange for libg2c.la to find libgcc_s.so in the build
>> tree, and then, after they're installed, the installed copy of
>> libg2c.so will find libgcc_s.so in the install tree.

> So can you help get the testsuite to use libtool so that this problem
> is resolved?

It depends on getting approval to use libtool for libgcc, which has
encountered some resistance in the past.  Before that, using libtool
for the testsuite won't get us at least this part of the benefit.


Unfortunately, using libtool in the testsuite is going to be a
significant undertaking.  The most significant reason is that libtool
can't be used to convert a source file directly to an executable.  It
needs separate compilation and linking steps, and the compilation step
must not be done using libtool because compiling with libtool is
useful to create libtool object files that are going into libtool
archives.  They *can* be used for executables, but you don't get any
benefit of using libtool for compilation of such object files, and it
can significantly degrade performance.

Anyway, testsuites that currently depend on the compiler driver being
able to compile and link in a single step have to be reworked such
that they can do it in two steps.  Then, it's going to be possible to
use libtool for the linking step, and get the benefit from it.  Still,
we need libgcc_s to be a libtool archive in order for libtool to
arrange for executables to know where to find libgcc_s at run time.

> You knew I was going to ask you, right? :-)

I must admit I didn't.  I never learn to keep my mouth shut :-)

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me