compatibility Clarification

[Rainer Orth]

Gabriel Dos Reis writes:

> | Ok, I'll try again.  Unfortunately, there are serious problems with the
> | current dejagnu based testsuite which links all tests with -static (PR
> | libstdc++/2841).
> 
> If I recall correctly, Benjamin indicates that because of libtool
> being gone there are some serious issues trying to link with 
> shared libs.  I don't have a clear picture of the whole issue.
> Please, anyone who undertands the issue, please feel free to educate
> me.

I think I've explained most of the issues in the above PR.  In short, you
have to teach the testsuite where to find the uninstalled shared libs
(namely in the respective .libs subdirectories) and augment dejagnu's
ld_library_path appropriately.  Much of this could probably be lifted from
the current g++ and objc testsuites, but I think much better than
duplicating this in several places, this knowledge should be consolidated
in one place, or better yet, libtool used directly to both link (as mkcheck
did before) and run (to set LD_LIBRARY_PATH appropriately, or whatever is
necessary so the platform's runtime linker correctly finds the uninstalled
shared library; mkcheck didn't do this) test programs under test.  This way
we could avoid duplicating both knowledge about libtool'ss inner workings
and details of the various shared library schemes in the dejagnu
testsuites.

	Rainer

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Rainer Orth, Faculty of Technology, Bielefeld University

Email: ro@TechFak.Uni-Bielefeld.DE