Auto merge of #146765 - Zalathar:rollup-ewh4s9o, r=Zalathar

Rollup of 10 pull requests

Successful merges:

 - rust-lang/rust#146229 (Automatically switch to lto-fat when flag RUSTFLAGS="- Zautodiff=Enable" is set)
 - rust-lang/rust#146484 (rustdoc-search: JavaScript optimization based on Firefox Profiler output)
 - rust-lang/rust#146541 (std: simplify host lookup)
 - rust-lang/rust#146615 (rustc_codegen_llvm: Feature Conversion Tidying)
 - rust-lang/rust#146638 (`rustc_next_trait_solver`: canonical out of `EvalCtxt`)
 - rust-lang/rust#146663 (Allow windows resource compiler to be overridden)
 - rust-lang/rust#146691 (std: Fix WASI implementation of `remove_dir_all`)
 - rust-lang/rust#146709 (stdarch subtree update)
 - rust-lang/rust#146738 (Fix tidy spellchecking on Windows)
 - rust-lang/rust#146740 (miri subtree update)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

.cirrus.yml

@@ -117,6 +117,8 @@ jobs:
           os: windows-2025
         - tuple: aarch64-pc-windows-msvc
           os: windows-11-arm
+        - tuple: arm64ec-pc-windows-msvc
+          os: windows-11-arm
         - tuple: x86_64-pc-windows-gnu
           os: windows-2025
         # - tuple: i686-pc-windows-gnu
@@ -207,14 +209,6 @@ jobs:
         rustup update nightly --no-self-update
         rustup default nightly
       shell: bash
-      if: matrix.target.os != 'windows-11-arm'
-    - name: Install Rust for `windows-11-arm` runners
-      # The arm runners don't have Rust pre-installed (https://github.com/actions/partner-runner-images/issues/77)
-      run: |
-        curl https://sh.rustup.rs | sh -s -- -y --default-toolchain nightly
-        echo "$HOME/.cargo/bin" >> $GITHUB_PATH
-      shell: bash
-      if: matrix.target.os == 'windows-11-arm'
 
     - run: rustup target add ${{ matrix.target.tuple }}
       shell: bash