Update Android compiler detection for NDK r25

[chriswailes]

This commit updates the compiler detection logic for the Android platform to work with NDK r25. This code is largely identical to the corresponding code in rustc/src/bootstrap/cc_detect.rs.

[chriswailes]

It occurs to me that if this is committed then developers using older versions of rustc (and targeting the corresponding Android NDK) but a new version of cc will encounter errors during compiler detection as the new paths will be returned. Ideally we would check on the compiler version to determine which version of the names to return. We could either do this using the rustversion crate (proc-macro) or using the rustc_version check (either in build.rs or in lib.rs directly as it is executed at build time as well).

Is there a preference between these options?

[thomcc]

Is there a preference between these options?

Getting the version by parsing the result of rustc --version is very simple (like 10-20loc tops) so I'd definitely prefer manually doing that rather than pulling in dependencies for this (one of those pulls in dependencies of its own for e.g. semver parsing, and the other is a proc macro).

You should probably get the path to rustc via the RUSTC env var, falling back to rustc if it's unset. I guess if that fails I might default to assuming a new version of rustc, to avoid a situation where the handling of old rustc breaks things for users of new rustc.

[thomcc]

Note to self: this shouldn't get merged until after the discussion in rust-lang/rust#103673 is fully resolved.

[chriswailes]

Thanks for the feedback. I'm in the middle of putting out some fires but I'll try and get to this ASAP.

[0xPoe]

@chriswailes Could we possibly move forward on this PR? It seems rust-lang/rust#105716 landed again.

[0xPoe]

@thomcc rust-lang/rust#103673 was closed now. Could you please take a look at this PR?

[NobodyXu]

This PR would need a rebase

[torokati44]

Do you think this could fix ruffle-rs/ruffle-android#62 ? 🤔