Meson: Remove unused build dependencies ppl and fplll

[tobiasdiez]

Remove ppl and fplll as build dependencies according to #39548 (comment). ppl is now declared as runtime dependency (in pyproject.toml but no longer mentioned in meson.build). fplll is completely removed since its only used via fpylll.

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[orlitzky]

What's different about ppl, do we use it outside of pplpy?

[tobiasdiez]

What's different about ppl, do we use it outside of pplpy?

I'm not sure. There is something called a MixedIntegerLinearProgram with argument ppl whose name at least suggests that it might call some executable. Do you know if we directly call/access ppl or is it only via pplpy?

[tornaria]

What's different about ppl, do we use it outside of pplpy?

I'm not sure. There is something called a MixedIntegerLinearProgram with argument ppl whose name at least suggests that it might call some executable. Do you know if we directly call/access ppl or is it only via pplpy?

I don't think there's any required executable. All that is needed at runtime is pplpy and its implied dependencies (i.e., the shared library libppl.so.14). Neither is necessary at build time.

[orlitzky]

PPL on Gentoo only installs two executables, /usr/bin/ppl-config and /usr/bin/ppl_pips. The first one is a pkg-config replacement, and the second doesn't turn up in grep, so I'm pretty confident that we don't use either at runtime.

For libppl, I've done a find ... xargs objdump -p on the sage install and nothing turned up. 🤷