Update linker-plugin-lto.md

[Takashiidobe]

The script provided doesn't have a clang LLVM version provided for Rust 1.49.0 or 1.50.0. Does anyone know why that might be?

[rust-highfive]

r? @GuillaumeGomez

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[GuillaumeGomez]

r? @pnkfelix

[pnkfelix]

We discussed this table in a recent T-compiler meeting, see zulip archive here

At that meeting, some made the observation that extending this table implies we are actively testing it, e.g. in our CI. But we are not actively testing it

I think our current plan is to shrink the table with a few example entries, rather than try to maintain it. In theory, one should be able to follow the instructions written in the doc to get the info one needs locally, namely this:

One can use rustc -vV in order to view the LLVM used by a given rustc version. Note that the version number given here is only an approximation as Rust sometimes uses unstable revisions of LLVM. However, the approximation is usually reliable.

[Takashiidobe]

That makes sense to me. I would be fine with a comment above this table in the code linking the above reasoning and in the future shrinking the table.