Pass --force-non-host unconditionally

action.yml

@@ -18,12 +18,6 @@ inputs:
   components:
     description: Comma-separated list of components to be additionally installed
     required: false
-  # Rustup 1.29.1 requires explicit opt-in for i686 toolchains on x64 Windows.
-  # https://github.com/rust-lang/rustup/pull/4935
-  force-non-host:
-    description: Allow installing and selecting a toolchain that does not match the host platform
-    required: false
-    default: "false"
 
 outputs:
   cachekey:
@@ -66,7 +60,6 @@ runs:
         echo "targets=$(for t in ${targets//,/ }; do echo -n ' --target' $t; done)" >> $GITHUB_OUTPUT
         echo "components=$(for c in ${components//,/ }; do echo -n ' --component' $c; done)" >> $GITHUB_OUTPUT
         echo "downgrade=${{steps.parse.outputs.toolchain == 'nightly' && inputs.components && ' --allow-downgrade' || ''}}" >> $GITHUB_OUTPUT
-        echo "force-non-host=${{inputs.force-non-host == 'true' && ' --force-non-host' || ''}}" >> $GITHUB_OUTPUT
       env:
         targets: ${{inputs.targets || inputs.target || ''}}
         components: ${{inputs.components}}
@@ -95,14 +88,16 @@ runs:
       if: runner.os == 'Windows'
       shell: bash
 
+    # Let rustc below check whether the requested toolchain can run on this host.
+    # This also permits i686 on x64 Windows: https://github.com/rust-lang/rustup/pull/4935.
     - name: rustup toolchain install ${{steps.parse.outputs.toolchain}}
-      run: rustup toolchain install ${{steps.parse.outputs.toolchain}}${{steps.flags.outputs.targets}}${{steps.flags.outputs.components}} --profile minimal${{steps.flags.outputs.downgrade}} --no-self-update${{steps.flags.outputs.force-non-host}}
+      run: rustup toolchain install ${{steps.parse.outputs.toolchain}}${{steps.flags.outputs.targets}}${{steps.flags.outputs.components}} --profile minimal${{steps.flags.outputs.downgrade}} --no-self-update --force-non-host
       env:
         RUSTUP_PERMIT_COPY_RENAME: 1
       shell: bash
 
     - name: rustup default ${{steps.parse.outputs.toolchain}}
-      run: rustup default ${{steps.parse.outputs.toolchain}}${{steps.flags.outputs.force-non-host}}
+      run: rustup default ${{steps.parse.outputs.toolchain}} --force-non-host
       shell: bash
       continue-on-error: true  # https://github.com/dtolnay/rust-toolchain/issues/127