Musl host toolchain
Based on https://github.com/rust-lang/rust/pull/55163 and https://github.com/rust-lang/rust/pull/57359
Depends on https://github.com/rust-lang/rust/pull/55566
CC https://github.com/rust-lang/rust/issues/57439
### How it works
Tested compiler made by `dist` on glibc and musl based distributions and verified binaries it produces:
* Ubuntu (glibc) - installed it as a target for host toolchain and observed no regressions for static (default) linking, dynamic linking apparently requires musl build libgcc so I didn't test it.
* Alpine (musl) - installed as the host toolchain, by default it links statically (executables are portable and work on glibc distributions) but with `-C target-feature=-crt-static` Rust flag it links dynamically (executables require musl built libraries).
### What's debatable
It should be decided whether this toolchain should link dynamically or statically when using it on musl distribution. I believe the distributions would prefer dynamic linking but it'd be misleading because `$ARCH-unknown-linux-musl` target links statically on the other hosts.
Another problem is using `RUSTFLAGS='-C target-feature=-crt-static'` for dynamic builds which is really uncomfortable.
To address both issues I suggest leaving `$ARCH-unknown-linux-musl` static for both host and cross target and introducing "alias triple" `$ARCH-unknown-linux-dynmusl`. It'd be the same as `$ARCH-unknown-linux-musl` (and use the same libraries to avoid duplication) but it'd link dynamically.
<del>
### Why it's still WIP (help wanted)
I'm having a hard time getting all tests to pass and I'd appreciate help.
Non-verbose error:
<details>
```
Testing proc_macro stage1 (x86_64-unknown-linux-musl -> x86_64-unknown-linux-musl)
Compiling proc_macro v0.0.0 (/checkout/src/libproc_macro)
error[E0463]: can't find crate for `std`
error[E0463]: can't find crate for `std`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0463`.
error: aborting due to previous error
For more information about this error, try `rustc --explain E0463`.
[RUSTC-TIMING] proc_macro test:true 0.529
[RUSTC-TIMING] proc_macro test:false 0.530
error: Could not compile `proc_macro`.
warning: build failed, waiting for other jobs to finish...
error: Could not compile `proc_macro`.
To learn more, run the command again with --verbose.
command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "test" "--target" "x86_64-unknown-linux-musl" "-j" "16" "--release" "--locked" "--manifest-path" "/checkout/src/libtest/Cargo.toml" "-p" "proc_macro" "--"
expected success, got: exit code: 101
failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test --host x86_64-unknown-linux-musl --target x86_64-unknown-linux-musl
```
</details>
Verbose error:
<details>
```
Testing proc_macro stage1 (x86_64-unknown-linux-musl -> x86_64-unknown-linux-musl)
Compiling proc_macro v0.0.0 (/checkout/src/libproc_macro)
Running `/checkout/obj/build/bootstrap/debug/rustc --edition=2018 --crate-name proc_macro src/libproc_macro/lib.rs --color never --crate-type lib --emit=dep-info,link -C opt-level=2 -C metadata=09ddd3ecc930ab63 -C extra-filename=-09ddd3ecc930ab63 --out-dir /checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/x86_64-unknown-linux-musl/release/deps --target x86_64-unknown-linux-musl -L dependency=/checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/x86_64-unknown-linux-musl/release/deps -L dependency=/checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/release/deps -C target-feature=-crt-static`
Running `/checkout/obj/build/bootstrap/debug/rustc --edition=2018 --crate-name proc_macro src/libproc_macro/lib.rs --color never --emit=dep-info,link -C opt-level=2 --test -C metadata=a564d363930469c8 -C extra-filename=-a564d363930469c8 --out-dir /checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/x86_64-unknown-linux-musl/release/deps --target x86_64-unknown-linux-musl -L dependency=/checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/x86_64-unknown-linux-musl/release/deps -L dependency=/checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/release/deps -C target-feature=-crt-static`
error[E0463]: can't find crate for `std`
error[E0463]: can't find crate for `std`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0463`.
error: aborting due to previous error
For more information about this error, try `rustc --explain E0463`.
[RUSTC-TIMING] proc_macro test:false 0.248
error: Could not compile `proc_macro`.
Caused by:
process didn't exit successfully: `/checkout/obj/build/bootstrap/debug/rustc --edition=2018 --crate-name proc_macro src/libproc_macro/lib.rs --color never --crate-type lib --emit=dep-info,link -C opt-level=2 -C metadata=09ddd3ecc930ab63 -C extra-filename=-09ddd3ecc930ab63 --out-dir /checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/x86_64-unknown-linux-musl/release/deps --target x86_64-unknown-linux-musl -L dependency=/checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/x86_64-unknown-linux-musl/release/deps -L dependency=/checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/release/deps -C target-feature=-crt-static` (exit code: 1)
warning: build failed, waiting for other jobs to finish...
[RUSTC-TIMING] proc_macro test:true 0.248
error: Could not compile `proc_macro`.
Caused by:
process didn't exit successfully: `/checkout/obj/build/bootstrap/debug/rustc --edition=2018 --crate-name proc_macro src/libproc_macro/lib.rs --color never --emit=dep-info,link -C opt-level=2 --test -C metadata=a564d363930469c8 -C extra-filename=-a564d363930469c8 --out-dir /checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/x86_64-unknown-linux-musl/release/deps --target x86_64-unknown-linux-musl -L dependency=/checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/x86_64-unknown-linux-musl/release/deps -L dependency=/checkout/obj/build/x86_64-unknown-linux-musl/stage1-test/release/deps -C target-feature=-crt-static` (exit code: 1)
command did not execute successfully: "/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo" "test" "--target" "x86_64-unknown-linux-musl" "-j" "16" "--release" "--locked" "--manifest-path" "/checkout/src/libtest/Cargo.toml" "--verbose" "-p" "proc_macro" "--"
expected success, got: exit code: 101
failed to run: /checkout/obj/build/bootstrap/debug/bootstrap test --host x86_64-unknown-linux-musl --target x86_64-unknown-linux-musl
```
</details>
Whole tests non-verbose output: [rust-tests.log](https://github.com/rust-lang/rust/files/2879945/rust-tests.log)
I think the error is because build system (correctly?) tries to use `obj/build/x86_64-unknown-linux-musl/stage1-test/x86_64-unknown-linux-musl/release/deps` which is empty but `obj/build/x86_64-unknown-linux-gnu/stage1-test/x86_64-unknown-linux-musl/release/deps` contains required libs.
</del>
The musl-target doesn't automatically disable static linking of musl when building a dylib, and then complains it can't build a dylib.
As a workaround, disable static linking via RUSTFLAGS, to see how far the build gets.
The proper fix is to have rustc figure that out automagically.
Update cargo
6 commits in 95b45eca19ac785263fed98ecefe540bb47337ac..0e35bd8af0ec72d3225c4819b330b94628f0e9d0
2019-03-06 19:24:30 +0000 to 2019-03-13 06:52:51 +0000
- Make `hg` optional for tests. (rust-lang/cargo#6739)
- Fingerprint build script deps only for path packages. (rust-lang/cargo#6734)
- Add --quiet option for `cargo test` (rust-lang/cargo#6358)
- .gitignore should end with a newline. (rust-lang/cargo#6732)
- Emit warning on misspelled environment variables (rust-lang/cargo#6694)
- Update glob requirement from 0.2.11 to 0.3.0 (rust-lang/cargo#6724)
resolve: Simplify import resolution for mixed 2015/2018 edition mode
Non-controversial part of https://github.com/rust-lang/rust/pull/57745.
Before:
| Local edition (per-span) | Global edition (--edition) | Imports (`use foo;`) | Absolute paths (`::foo`) |
| ------------- |----------------|-----------------------------------------|------------------------------------------------|
| 2018 | Any | Uniform | Extern prelude |
| 2015 | 2015 | Crate-relative | Crate-relative |
| 2015 | 2018 | Crate-relative with fallback to Uniform (future-proofed to error if the result is not Crate-relative or from Extern prelude) | Crate-relative with fallback to Extern prelude |
After:
| Local edition (per-span) | Global edition (--edition) | Imports (`use foo;`) | Absolute paths (`::foo`) |
| ------------- |----------------|-----------------------------------------|------------------------------------------------|
| 2018 | Any | Uniform | Extern prelude |
| 2015 | 2015 | Crate-relative | Crate-relative |
| 2015 | 2018 | Crate-relative with fallback to Extern prelude | Crate-relative with fallback to Extern prelude |
I.e. only the behavior of the mixed local-2015-global-2018 mode is changed.
This mixed mode has two goals:
- Address regressions from https://github.com/rust-lang/rust/pull/56053#issuecomment-440826397.
Both "before" and "after" variants address those regressions.
- Be retrofit-able to "full 2015" edition (https://github.com/rust-lang/rust/pull/57745).
Any more complex fallback scheme (with more candidates) than "Crate-relative with fallback to Extern prelude" will give more regressions than https://github.com/rust-lang/rust/pull/57745#issuecomment-455855089 and is therefore less retrofit-able while also being, well, more complex.
So, we can settle on "Crate-relative with fallback to Extern prelude".
(I'll hopefully proceed with https://github.com/rust-lang/rust/pull/57745 after mid-February.)
r? @Centril
Rollup of 16 pull requests
Successful merges:
- #58829 (librustc_interface: Update scoped-tls to 1.0)
- #58876 (Parse lifetimes that start with a number and give specific error)
- #58908 (Update rand version)
- #58998 (Fix documentation of from_ne_bytes and from_le_bytes)
- #59056 (Use lifetime contravariance to elide more lifetimes in core+alloc+std)
- #59057 (Standardize `Range*` documentation)
- #59080 (Fix incorrect links in librustc_codegen_llvm documentation)
- #59083 (Fix#54822 and associated faulty tests)
- #59093 (Remove precompute_in_scope_traits_hashes)
- #59101 (Reduces Code Repetitions like `!n >> amt`)
- #59121 (impl FromIterator for Result: Use assert_eq! instead of assert!)
- #59124 (Replace assert with assert_eq)
- #59129 (Visit impl Trait for dead_code lint)
- #59130 (Note that NonNull does not launder shared references for mutation)
- #59132 (ignore higher-ranked object bound conditions created by WF)
- #59138 (Simplify Iterator::{min, max})
Failed merges:
r? @ghost
Simplify Iterator::{min, max}
This PR simplifies the `select_fold1` helper method used to implmement `Iterator::{min, min_by, min_by_key, max, max_by, max_by_key}` by removing the projection argument, which was only used by the implementations of `min_by_key` and `max_by_key`.
I also added tests to ensure that the stability as mentioned in the comments of `min` and `max` is preserved, and fixed the `iter::{bench_max, bench_max_by_key}` benchmarks which the compiler presumably was able to collapse into closed-form expressions. None of the benchmark results were impacted, I suspect their generated assembly didn't change.
