cranelift-codegen: add feature to explicitly enable the host ISA #6551
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This makes sense to me, thanks for the great explanation!
It is needed because cargo features are additive. Given a situation where you have two dependencies: * One depends on cranelift aarch64 codegen, so it enables the `aarch64` feature. * The other depends on cranelift native codegen, so it does not enable any arch feature. Given the additive property of features, cranelift-codegen will be built with the `aarch64` feature for both dependencies (assuming they use the same cranelift version), so the native ISA will not be included (unless it is aarch64). With the `host-arch` feature added here, the native host ISA can now be explicitly requested without risk of another crate of the dependency tree disabling it.
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…ecodealliance#6551) It is needed because cargo features are additive. Given a situation where you have two dependencies: * One depends on cranelift aarch64 codegen, so it enables the `aarch64` feature. * The other depends on cranelift native codegen, so it does not enable any arch feature. Given the additive property of features, cranelift-codegen will be built with the `aarch64` feature for both dependencies (assuming they use the same cranelift version), so the native ISA will not be included (unless it is aarch64). With the `host-arch` feature added here, the native host ISA can now be explicitly requested without risk of another crate of the dependency tree disabling it.
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It is needed because cargo features are additive. Given a situation where you have two dependencies:
aarch64feature.Given the additive property of features, cranelift-codegen will be built with the
aarch64feature for both dependencies (assuming they use the same cranelift version), so the native ISA will not be included (unless it is aarch64).With the
host-archfeature added here, the native host ISA can now be explicitly requested without risk of another crate of the dependency tree disabling it.The native ISA is still enabled when none is explicitly enabled, although I think that this behaviour should be deprecated.