From 79c80c4ec44a470e3b9cb194da19a23a2ddb2f0a Mon Sep 17 00:00:00 2001 From: Isaac Woods Date: Mon, 17 Sep 2018 19:33:52 +0100 Subject: Re-export core::ffi::c_void if supported --- build.rs | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 build.rs (limited to 'build.rs') diff --git a/build.rs b/build.rs new file mode 100644 index 0000000000..aa56ea0545 --- /dev/null +++ b/build.rs @@ -0,0 +1,35 @@ +use std::env; +use std::process::Command; +use std::str; + +fn main() { + /* + * If `core::ffi::c_void` exists, libc can just re-export it. Otherwise, it + * must define an incompatible type to retain backwards-compatibility. + */ + if rustc_minor_version().expect("Failed to get rustc version") >= 31 { + println!("cargo:rustc-cfg=core_cvoid"); + } +} + +fn rustc_minor_version() -> Option { + macro_rules! otry { + ($e:expr) => { + match $e { + Some(e) => e, + None => return None, + } + }; + } + + let rustc = otry!(env::var_os("RUSTC")); + let output = otry!(Command::new(rustc).arg("--version").output().ok()); + let version = otry!(str::from_utf8(&output.stdout).ok()); + let mut pieces = version.split('.'); + + if pieces.next() != Some("rustc 1") { + return None; + } + + otry!(pieces.next()).parse().ok() +} -- cgit v1.2.1