Simple size optimization flags for Cargo by default #552
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Add a few arguments to Cargo/rustc to optimize better for code size
alistair23
approved these changes
Jun 19, 2024
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Very simply add three Cargo flags by default that seem to have a reasonable impact on code size in many examples, all used in the kernel as well:
opt-level = "z"is LLVM's-Os, i.e., optimize for size not speed, please. This seems to help in all but very small examples (under 1k)codegen-units = 1restricts Cargo from splitting crates up during compilation and in general should improve LTO the cost is slower compile times. In practice, this doesn't seem to make a difference in this repo for now, so this is mostly a forward thinking precaution.