message: Rerun minijail build.rs if a source file changed
  This covers only the basic case of a modified c source
  file. No dependency calculation!
diff: @@ -104,23 +104,29 @@ fn main() -> io::Result<()> {
  .expect("Faild to get CARGO_MANIFEST_DIR")
  .join("../..");
  + let sources = &[
  + "../../bpf.c",
  + "../../libminijail.c",
  + "../../signal_handler.c",
  + "../../syscall_filter.c",
  + "../../syscall_wrapper.c",
  + "../../system.c",
  + "../../util.c",
  + ];
  +
  cc::Build::new()
  .define("ALLOW_DEBUG_LOGGING", "1")
  .define("PRELOADPATH", "\"invalid\"")
  .flag("-Wno-implicit-function-declaration")
  - .file("../../bpf.c")
  - .file("../../libminijail.c")
  - .file("../../signal_handler.c")
  - .file("../../syscall_filter.c")
  - .file("../../syscall_wrapper.c")
  - .file("../../system.c")
  - .file("../../util.c")
  + .files(sources)
  .file(generate_syscall_constants(&target_os)?)
  .file(generate_syscall_table()?)
  .include(minijail_dir)
  .compile("minijail");
  - // TODO: emit proper cargo:rerun-if-changed
  + sources
  + .iter()
  + .for_each(|s| println!("cargo:rerun-if-changed={}", s));
  println!("cargo:rustc-link-lib=static=minijail");
  