Auto merge of rust-lang#105845 - lqd:revert-thinlto-revert, r=Mark-Si…

…mulacrum

Re-enable ThinLTO for rustc on `x86_64-apple-darwin`

ThinLTO was disabled on x64 mac in rust-lang#105646 because of the rust-lang#105637 regression.

It was later discovered that the issue was present on other targets as well, as the mac revert was already landing. The linux/win reverts, however, did not land before the root cause was identified.

rust-lang#105800 fixed the underlying issue in `-Zdylib-lto` handling, and the x64 msvc and linux targets are now fixed, ICEs are using the correct `rustc_driver` panic hook.

This PR re-enables ThinLTO on mac for improved perf now that the issue should be fixed everywhere.

.github/workflows/ci.yml

@@ -301,7 +301,7 @@ jobs:
           - name: dist-x86_64-apple
             env:
               SCRIPT: "./x.py dist bootstrap --include-default-paths --host=x86_64-apple-darwin --target=x86_64-apple-darwin"
-              RUST_CONFIGURE_ARGS: "--enable-full-tools --enable-sanitizers --enable-profiler --set rust.jemalloc --set llvm.ninja=false"
+              RUST_CONFIGURE_ARGS: "--enable-full-tools --enable-sanitizers --enable-profiler --set rust.jemalloc --set llvm.ninja=false --set rust.lto=thin"
               RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
               MACOSX_DEPLOYMENT_TARGET: 10.7
               SELECT_XCODE: /Applications/Xcode_13.4.1.app

src/ci/github-actions/ci.yml

@@ -467,7 +467,7 @@ jobs:
           - name: dist-x86_64-apple
             env:
               SCRIPT: ./x.py dist bootstrap --include-default-paths --host=x86_64-apple-darwin --target=x86_64-apple-darwin
-              RUST_CONFIGURE_ARGS: --enable-full-tools --enable-sanitizers --enable-profiler --set rust.jemalloc --set llvm.ninja=false
+              RUST_CONFIGURE_ARGS: --enable-full-tools --enable-sanitizers --enable-profiler --set rust.jemalloc --set llvm.ninja=false --set rust.lto=thin
               RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
               MACOSX_DEPLOYMENT_TARGET: 10.7
               SELECT_XCODE: /Applications/Xcode_13.4.1.app