Re: Addressing sources dynamically generated by autoconf

[Jan Engelhardt]

On Monday 2022-11-21 16:22, Thomas Jahns wrote:

>The question consequently is: how would I create a Makefile.am that accounts
>for a list of C sources, when the sources are not yet present/known from the
>perspective of automake?

I don't see that working even without automake. Once make has loaded a
Makefile, the internal DAG is immutable for all practical considerations. If
you do not have the source names, what would you give the compiler? Which
compiler would you even invoke if you do not know whether you are going to have
a C or C++ file?

That is why source file names ought to be known, even if the file itself is
empty, absent-until-later, or remains completely unused due to conditionals
along the way.

>While installing a fixed MPI library might seem to be the correct way to
>handle the issue, our users are not typically in a position to demand this

root is not needed. They can install the fixed MPI library to
/home/self, use LD_LIBRARY_PATH at runtime and

 ./configure CPPFLAGS=-I/home/self/include LDFLAGS="-L/home/self/lib
 -Wl,-rpath,/home/self/lib"

for build-time. The upside is that neither libyaxt nor libzzzzzz need to bother
producing a fixed MPI on their own, individually, which slims down all these
projects.