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rustrust-cargo

How can I force `build.rs` to run again without cleaning my whole project?

How can I force build.rs to run again without cleaning my whole project? I checked cargo build --help but I couldn't find anything related to build.rs.

Solution

  • If you print 

    "cargo:rerun-if-changed=<FILE>"

    the build will be triggered every time the file has changed.

    rerun-if-changed=PATH is a path to a file or directory which indicates that the build script should be re-run if it changes (detected by a more-recent last-modified timestamp on the file). Normally build scripts are re-run if any file inside the crate root changes, but this can be used to scope changes to just a small set of files. -- source

    I'm not aware of a solution without changing a file manually (I just put a whitespace anywhere in my build.rs, it will be removed by rustfmt though).

    I have several buildscripts in my projects, and mostly these two lines give me a nice solution:

    println!("cargo:rerun-if-changed=build.rs");
println!("cargo:rerun-if-changed=path/to/Cargo.lock");

    but I guess you are looking for a command rustc/cargo command. Anyway, you can put in a small script, which will edit a certain file, which will trigger the build-process.