rust/chg/build.rs

phabricator: add a config knob to import in the secret phase

For my use anyway, it's better to have a config knob that's always set than to
try to remember a switch.  But we can add a tristate switch if desired.

Differential Revision: https://phab.mercurial-scm.org/D8137

extern crate cc;

fn main() {
    cc::Build::new()
        .warnings(true)
        .file("src/sendfds.c")
        .file("src/sighandlers.c")
        .compile("procutil");
}