Make lib.rs accessible to dependers

[vojtechkral]

Hi,
we are trying to use svd2rust from a build.rs file. As of now, cargo build-dependencies can't be binaries and using svd2rust as a dependency yields an empty crate. svd2rust has to be installed manually for our build.rs to work.

This is a proposal to fix that. I'm not sure this patch is the right way, but it seems all we need is access to the generate() function and we're good to go.

Thanks!

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @therealprof (or someone else) soon.

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[therealprof]

I though there was a similar PR to this but I can't find it. Sounds good to me in principle but I'm not a very keen user of build.rs so I'd like to hear other opinions.

CC @rust-embedded/tools

[Emilgardis]

#214 did indeed do this. I can't reproduce the mentioned issue when using latest changes (currently unreleased, candidate for 0.15) in cargo 1.33.0 (2019-02-12). Unless there's a good reason to add this I think this should be closed.

[vojtechkral]

Yes, using the current master, it seems to work as expected. I must've gotten 0.14 and master mixed up, sorry.

Is there an ETA for 0.15?