Return instead of co_await in dispatch_setup_packet - #2
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Every branch hands off to exactly one async call with nothing else in the function, so it can return that call's future directly instead of paying for its own coroutine frame/resume state just to await and immediately finish.
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Summary
dispatch_setup_packet()is a switch where every branch does exactly one async call and nothing else before or after it. It doesn't own any local state the async chain depends on (p_requestis a reference into the caller's frame). That means it canreturnthe chosen call's future directly instead ofco_await-ing it, dropping its own coroutine frame/resume-state machinery entirely.libhal-arm-mcuv2 USB CDC demo: 75,373 → 74,949 bytes flash (.text+.rodata+unwind tables), a 424 byte reduction, with no behavior change.Test plan
conan create . -pr:a hal/tc/llvm -pr hal/mcu/stm32f103zg --build=missing— builds and test_package runslibhal-arm-mcu's demos against this version — all 8 demos build clean, USB CDC demo confirmed smaller