Update deployment target setup in jobs.yml

Note that specifying MACOSX_STD_DEPLOYMENT_TARGET is still completely
unnecessary here, but it's nice to have for future changes where we
might want to version `std` and `rustc`'s deployment target separately.

src/ci/github-actions/jobs.yml

@@ -59,6 +59,7 @@ envs:
     SCRIPT: ./x.py --stage 2 test --skip tests/ui --skip tests/rustdoc -- --exact
     RUST_CONFIGURE_ARGS: --build=x86_64-apple-darwin --enable-sanitizers --enable-profiler --set rust.jemalloc
     RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
+    # Ensure that host tooling is tested on our minimum supported macOS version.
     MACOSX_DEPLOYMENT_TARGET: 10.12
     MACOSX_STD_DEPLOYMENT_TARGET: 10.12
     SELECT_XCODE: /Applications/Xcode_15.2.app
@@ -370,7 +371,9 @@ auto:
       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 rust.lto=thin --set rust.codegen-units=1
       RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
+      # Ensure that host tooling is built to support our minimum support macOS version.
       MACOSX_DEPLOYMENT_TARGET: 10.12
+      MACOSX_STD_DEPLOYMENT_TARGET: 10.12
       SELECT_XCODE: /Applications/Xcode_15.2.app
       NO_LLVM_ASSERTIONS: 1
       NO_DEBUG_ASSERTIONS: 1
@@ -386,7 +389,10 @@ auto:
       # https://github.com/rust-lang/rust/issues/129069
       RUST_CONFIGURE_ARGS: --enable-sanitizers --enable-profiler --set rust.jemalloc --set target.aarch64-apple-ios-macabi.sanitizers=false --set target.x86_64-apple-ios-macabi.sanitizers=false
       RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
+      # Ensure that host tooling is built to support our minimum support macOS version.
+      # FIXME(madsmtm): This might be redundant, as we're not building host tooling here (?)
       MACOSX_DEPLOYMENT_TARGET: 10.12
+      MACOSX_STD_DEPLOYMENT_TARGET: 10.12
       SELECT_XCODE: /Applications/Xcode_15.2.app
       NO_LLVM_ASSERTIONS: 1
       NO_DEBUG_ASSERTIONS: 1
@@ -404,7 +410,6 @@ auto:
       <<: *env-x86_64-apple-tests
     <<: *job-macos-xl
 
-  # This target only needs to support 11.0 and up as nothing else supports the hardware
   - name: dist-aarch64-apple
     env:
       SCRIPT: ./x.py dist bootstrap --include-default-paths --host=aarch64-apple-darwin --target=aarch64-apple-darwin
@@ -419,6 +424,8 @@ auto:
       RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
       SELECT_XCODE: /Applications/Xcode_15.4.app
       USE_XCODE_CLANG: 1
+      # Aarch64 tooling only needs to support macOS 11.0 and up as nothing else
+      # supports the hardware.
       MACOSX_DEPLOYMENT_TARGET: 11.0
       MACOSX_STD_DEPLOYMENT_TARGET: 11.0
       NO_LLVM_ASSERTIONS: 1
@@ -428,7 +435,6 @@ auto:
       CODEGEN_BACKENDS: llvm,cranelift
     <<: *job-macos-m1
 
-  # This target only needs to support 11.0 and up as nothing else supports the hardware
   - name: aarch64-apple
     env:
       SCRIPT: ./x.py --stage 2 test --host=aarch64-apple-darwin --target=aarch64-apple-darwin
@@ -439,6 +445,8 @@ auto:
       RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
       SELECT_XCODE: /Applications/Xcode_15.4.app
       USE_XCODE_CLANG: 1
+      # Aarch64 tooling only needs to support macOS 11.0 and up as nothing else
+      # supports the hardware, so only need to test it there.
       MACOSX_DEPLOYMENT_TARGET: 11.0
       MACOSX_STD_DEPLOYMENT_TARGET: 11.0
       NO_LLVM_ASSERTIONS: 1