cargo-rustc

Compile a package with extra rustc flags

TLDR

Compile with extra rustc flags

$ cargo rustc -- [rustc_flags]

Compile specific binary with flags

$ cargo rustc --bin [name] -- [flags]

Compile library with flags

$ cargo rustc --lib -- [-C opt-level=3]

Enable specific codegen option

$ cargo rustc -- -C [target-cpu=native]

Add link arguments

$ cargo rustc -- -C [link-arg=-fuse-ld=lld]

cargo rustc compiles the current package and passes extra options directly to the Rust compiler. Unlike `RUSTFLAGS`, which applies flags to all crates in the build, arguments after `--` are passed only to the final compiler invocation for the specified target, not to its dependencies.This command is useful for enabling specific codegen options, changing optimization levels, emitting intermediate representations like LLVM IR or assembly, or passing custom linker arguments for a single crate without affecting the rest of the dependency graph.

PARAMETERS

--lib

Compile library only

--bin name

Compile specified binary

--bins

Compile all binaries

--example name

Compile specified example

--test name

Compile specified test

--bench name

Compile specified benchmark

-r, --release

Use release profile

--profile name

Use specified profile

-p, --package spec

Package to compile

--target triple

Target platform

-j, --jobs n

Parallel jobs

--features features

Enable features

--all-features

Enable all features

RUSTC OPTIONS

Common rustc flags:- -C opt-level=N: Optimization level- -C target-cpu=NAME: Target CPU- -C link-arg=ARG: Linker argument- --emit=TYPE: Output type (asm, llvm-ir, obj)