rust/compiler/rustc_target
Dylan DPC 37df40bd1c
Rollup merge of #77202 - ehuss:defer-apple-sdkroot, r=petrochenkov
Defer Apple SDKROOT detection to link time.

This defers the detection of the SDKROOT for Apple iOS/tvOS targets to link time, instead of when the `Target` is defined. This allows commands that don't need to link to work (like `rustdoc` or `rustc --print=target-list`). This also makes `--print=target-list` a bit faster.

This also removes the note in the platform support documentation about these targets being missing. When I wrote it, I misunderstood how the SDKROOT stuff worked.

Notes:
* This means that JSON spec targets can't explicitly override these flags. I think that is probably fine, as I believe the value is generally required, and can be set with the SDKROOT environment variable.
* This changes `x86_64-apple-tvos` to use `appletvsimulator`. I think the original code was wrong (it was using `iphonesimulator`). Also, `x86_64-apple-tvos` seems broken in general, and I cannot build it locally. The `data_layout` does not appear to be correct (it is a copy of the arm64 layout instead of the x86_64 layout). I have not tried building Apple's LLVM to see if that helps, but I suspect it is just wrong (I'm uncertain since I don't know how the tvOS simulator works with its bitcode-only requirements).
* I'm tempted to remove the use of `Result` for built-in target definitions, since I don't think they should be fallible. This was added in https://github.com/rust-lang/rust/pull/34980, but that only relates to JSON definitions. I think the built-in targets shouldn't fail. I can do this now, or not.

Fixes #36156
Fixes #76584
2020-10-01 02:13:34 +02:00
..
src Rollup merge of #77202 - ehuss:defer-apple-sdkroot, r=petrochenkov 2020-10-01 02:13:34 +02:00
Cargo.toml mv compiler to compiler/ 2020-08-30 18:45:07 +03:00
README.md mv compiler to compiler/ 2020-08-30 18:45:07 +03:00

librustc_target contains some very low-level details that are specific to different compilation targets and so forth.

For more information about how rustc works, see the rustc dev guide.