Re: have-lib: ‘additional_libdir’ set to ‘PREFIX/lib64’

[Bruno Haible]

Hi Ludovic,

> When passed ‘--with-PACKAGE-prefix=/p’, ‘AC_LIB_LINKFLAGS_BODY’
> deduces ‘additional_libdir=/p/lib64’ on x86_64.

Yes, this is expected on the common bi-arch Linux systems.

> This doesn’t work on NixOS which doesn’t (quite) support multilib, and
> where libs are to be found under ‘/p/lib’.  Unfortunately, this leads
> ‘AC_LIB_LINKFLAGS_BODY’ to ignore the ‘/p’ prefix altogether, both for
> includes and libs (it ends up in the “Didn't find the library” case).
> 
> A simple fix would be to add a ‘--with-PACKAGE-lib’ (and optionally
> ‘--with-PACKAGE-include’) option.

You can just as well set CPPFLAGS and LDFLAGS manually, then. Recall that
the --with-PACKAGE-prefix option is merely a shortcut for what can
be specified by setting CPPFLAGS and LDFLAGS appropriately.

This will placate the real problem. The real problem is that on a system
where gcc knows to find 64-bit libraries under /usr/lib64, NixOS will -
according to what you say - use a different naming convention than what
the rest of the system does. User confusion is guaranteed.

Bruno