Set CARGO_PROFILE_dev_OPT_LEVEL=0.
CARGO_PROFILE_dev_OPT_LEVEL=0
ref: https://doc.rust-lang.org/cargo/reference/environment-variables.html
CARGO_PROFILE_<name>_OPT_LEVEL — Set the optimization level, see profile.<name>.opt-level.
CARGO_PROFILE_<name>_OPT_LEVEL
profile.<name>.opt-level