This reverts commit faac70b.

Signed-off-by: onur-ozkan <work@onurozkan.dev>

I believe this was changed a while ago in rust-lang/promote-release#14.

When using `symlink_dir`, it first removes the existing link with `remove_dir`.
However, if the path isn't a link and contains files, `remove_dir` fails
with "DirectoryNotEmpty", which causes the symbolic linking to fail as well.
We have this problem on linking 'rustlib/rust' because it contains files as an
actual directory.

Signed-off-by: onur-ozkan <work@onurozkan.dev>

If `codegen-backends` is missing "cranelift" and "gcc" (which is common),
bootstrap will now only show this warning during `dist` and `install` steps,
or if codegen-backends was explicitly called for build.

Signed-off-by: onur-ozkan <work@onurozkan.dev>

This is already handled from bootstrap at
https://github.com/rust-lang/rust/blob/a1ca449981e3b8442e358026437b7bedb9a1458e/src/bootstrap/src/utils/helpers.rs#L504-L506.

Signed-off-by: onur-ozkan <work@onurozkan.dev>

This will make it easier to keep `f16` and `f128` consistent as their
implementations get added.

Better explain the reasoning for the `next_up`/`next_down` integer
implementation, as requested by Ralf.

There are some complexities about what platforms we can test f16 and
f128 on.  Put this in build.rs so we have an easy way to configure tests
with a single attribute, and keep it up to date.

The symbols that these tests rely on are not available on all platforms
and some ABIs are buggy, tests that rely on external functions are
configured to only run on x86 (`f128`) or aarch64 (`f16`).

This adds everything that was directly or transitively blocked on const
arithmetic for these types, which was recently merged.

Since const arithmetic is recent, most of these need to be gated by
`bootstrap`.

Anything that relies on intrinsics that are still missing is excluded.

This suite tests all library functions that are now available for the
types. Tests are only run on certain platforms where `f16` and `f128`
are known to work (have symbols available and don't crash LLVM).

So we can omit the `token::` qualifier, which gives more space to some
cramped code.

Merge `PatParam`/`PatWithOr`, and `Expr`/`Expr2021`, for a few reasons.

- It's conceptually nice, because the two pattern kinds and the two
  expression kinds are very similar.

- With expressions in particular, there are several places where both
  expression kinds get the same treatment.

- It removes one unreachable match arm.

- Most importantly, for rust-lang#124141 I will need to introduce a new type
  `MetaVarKind` that is very similar to `NonterminalKind`, but records a
  couple of extra fields for expression metavars. It's nicer to have a
  single `MetaVarKind::Expr` expression variant to hold those extra
  fields instead of duplicating them across two variants
  `MetaVarKind::{Expr,Expr2021}`. And then it makes sense for patterns
  to be treated the same way, and for `NonterminalKind` to also be
  treated the same way.

I also clarified the comments, because I have long found them a little
hard to understand.

…-Simulacrum

tidy: skip submodules if not present for non-CI environments

Right now tidy requires rustc-perf to be fetched as it checks its license, but this doesn't make sense for most contributors since rustc-perf is a dist-specific tool and its license will not change frequently, especially during compiler development. This PR makes tidy to skip rustc-perf if it's not fetched and if it's not running in CI.

Applies rust-lang#126225 (comment) and reverts rust-lang#126225.

…Simulacrum

Add more constants, functions, and tests for `f16` and `f128`

This adds everything that was in some way blocked on const eval, since rust-lang#126429 landed. There is a lot of `cfg(bootstrap)` since that is a fairly recent change.

`f128` tests are disabled on everything except x86_64 and Linux aarch64, which are two platforms I know have "good" support for these types - meaning basic math symbols are available and LLVM doesn't hit selection crashes. `f16` tests are enabled on almost everything except for known LLVM crashes. Doctests are only enabled on x86_64.

Tracking issue: rust-lang#116909

…k-Simulacrum

Update outdated README in build-manifest.

I believe this was changed a while ago in rust-lang/promote-release#14.

…imulacrum

less bootstrap warnings

This is how the build logs looks like currently:

```sh
$ x build
Building bootstrap
   Compiling bootstrap v0.0.0 (/home/nimda/devspace/onur-ozkan/rust/src/bootstrap)
    Finished `dev` profile [unoptimized] target(s) in 3.43s
WARNING: no codegen-backends config matched the requested path to build a codegen backend. HELP: add backend to codegen-backends in config.toml.
WARNING: creating symbolic link `/home/nimda/devspace/.other/rustc-builds/build/x86_64-unknown-linux-gnu/stage2/lib/rustlib/rustc-src/rust` to `/home/nimda/devspace/onur-ozkan/rust` failed with File exists (os
error 17)
Creating a sysroot for stage2 compiler (use `rustup toolchain link 'name' build/host/stage2`)
WARNING: creating symbolic link `/home/nimda/devspace/.other/rustc-builds/build/x86_64-unknown-linux-gnu/ci-rustc-sysroot/lib/rustlib/rustc-src/rust` to `/home/nimda/devspace/onur-ozkan/rust` failed with File e
xists (os error 17)
Building tool rustdoc (stage1 -> stage2, x86_64-unknown-linux-gnu)
   Compiling rustdoc v0.0.0 (/home/nimda/devspace/onur-ozkan/rust/src/librustdoc)
   Compiling rustdoc-tool v0.0.0 (/home/nimda/devspace/onur-ozkan/rust/src/tools/rustdoc)
    Finished `release` profile [optimized + debuginfo] target(s) in 13.57s
Build completed successfully in 0:00:17
```

This PR removes artifact linking warnings and only shows the codegen-backend warning if explicitly called or during Dist or Install steps.

…mulacrum

remove `GIT_DIR` handling in pre-push hook

This is already handled from bootstrap: https://github.com/rust-lang/rust/blob/a1ca449981e3b8442e358026437b7bedb9a1458e/src/bootstrap/src/utils/helpers.rs#L504-L506

…iler-errors

make unsized_fn_params an internal feature

As suggested [here](rust-lang#123894 (comment)).
r? ``@compiler-errors``

Fixes rust-lang#123887 (kind of -- ICEs on internal features are considered acceptable so this issue is not-a-bug once this PR lands)

…compiler-errors

don't ICE when encountering an extern type field during validation

"extern type" is a pain that keeps on giving...

Fixes rust-lang#126814

r? ``@oli-obk``

…errors

delegation: Do not crash on qpaths without a trait

Fixes rust-lang#126742

…r=compiler-errors

Rework pattern and expression nonterminal kinds.

Some tweaks to `NonterminalKind` that will assist with rust-lang#124141. Details in the individual commits.

r? compiler-errors
cc ``@eholk``