ccfg

Build-script helpers for crates that compile C code via the cc crate.

Installation

[build-dependencies]
ccfg = { version = "0.1", features = ["build"] }

The build feature gates the cc dependency so it is only pulled in when building build.rs, not in the final binary.

Usage

// build.rs
fn main() {
    let mut build = cc::Build::new();
    build.file("src/c_src/re.c");

    ccfg::configure_arch(&mut build);
    ccfg::apply_coverage(&mut build);

    build.compile("re");
}

configure_arch

Configures the compiler for the current target:

• Zephyr cross-compilation — when ZEPHYR_BASE is set and no CC/TARGET_CC override is present, reads CMAKE_C_COMPILER from CMakeCache.txt and sets it as the compiler. This is the only reliable source for the cross-compiler path inside a west workspace.
• riscv64 — adds -mcmodel=medany so relocations work when Zephyr places the binary outside the low-2 GB address window.

Emits the appropriate cargo:rerun-if-changed and cargo:rerun-if-env-changed directives as side effects.

apply_coverage

Reconfigures build for LLVM source-based coverage when the calling crate's coverage Cargo feature is active. Sets the compiler to Clang, forces -O0, and adds -fprofile-instr-generate/-fcoverage-mapping. No-op otherwise.

Must be called after any build.opt_level() call, as it overrides that setting.

License

Apache-2.0 — see LICENSE.