Re: gmp-4.0.1: Inter-library dependencies vs. DESTDIR installation

[Kevin Ryde]

Christian Cornelssen <address@hidden> writes:
>
> I first thought of directly integrating the libgmp object files into
> libgmpxx.la.

That'd be a possibility, though a bit wasteful.

> This would work in all environments and might allow
> optimization of subroutine calls within the library (if the linker
> supports that), thereby increasing performance.

On x86 I think that optimization normally only happens if you ask for
-Bsymbolic.  (The same optimization at compile-time would be even
better, per some cryptic notes in mpn/x86/README.)

> Perhaps that's an idea.

Be nice if libtool could address this itself eventually.  For now I'll
add the following few words to the "Known build problems" in the
manual.


`DESTDIR' and shared `libgmpxx'
     `make install DESTDIR=/my/staging/area' or the same with a `prefix'
     override to install to a temporary directory may fail when
     building a shared version of `libgmpxx'.

     If `libgmp' is already installed in its final location then
     there's no problem, but if not then unfortunately libtool doesn't
     know to look in the temporary directory for `libgmp' when
     relinking `libgmpxx'.

     A workaround, at least for SVR4 style systems such as GNU/Linux,
     is to insert a suitable `-L' in the `relink_command' of
     `libgmpxx.la' after building but before installing.  This can be
     automated with something like

          sed '/^relink_command/s:libgmp.la:-L /my/staging/area libgmp.la:' \
              <libgmpxx.la >libgmpxx.new
          mv libgmpxx.new libgmpxx.la