build.rs: set CMAKE_INSTALL_PREFIX (#51)

Author: Jason Mobarak

build.rs

@@ -1,11 +1,17 @@
 extern crate bindgen;
 
-use cmake::Config;
 use std::env;
 use std::path::PathBuf;
 
 fn main() {
-    let dst = Config::new("third-party/libswiftnav/").build();
+    let mut cmake = cmake::Config::new("third-party/libswiftnav/");
+    let out_dir = env::var("OUT_DIR").unwrap();
+
+    cmake
+        .profile("Release")
+        .define("CMAKE_INSTALL_PREFIX", out_dir);
+
+    let dst = cmake.build();
 
     println!("cargo:rustc-link-search=native={}/lib/", dst.display());
     println!("cargo:rustc-link-lib=static=swiftnav");