#[cfg(feature="pkg-config")]
extern crate "pkg-config" as pkg_config;

fn main() {
    if !build_pkgconfig() {
      println!("cargo:rustc-flags=-l SDL2");
    }
}

#[cfg(not(feature="pkg-config"))]
fn build_pkgconfig() -> bool {
    false
}

#[cfg(feature="pkg-config")]
fn build_pkgconfig() -> bool {
    if pkg_config::find_library("sdl2").is_err() {
        panic!("Could not find SDL2 via pkgconfig");
    }
    true
}

#[cfg(feature="pkg-config")]
extern crate "pkg-config" as pkg_config;

fn main() {
    if !build_pkgconfig() {
      println!("cargo:rustc-flags=-l SDL2");
    }
}

#[cfg(not(feature="pkg-config"))]
fn build_pkgconfig() -> bool {
    false
}

#[cfg(feature="pkg-config")]
fn build_pkgconfig() -> bool {
    let opts = pkg_config::default_options("sdl2");
    if pkg_config::find_library_opts("sdl2", &opts).is_err() {
        panic!("Could not find SDL2 via pkgconfig");
    }
    true
}

--- 
+++ 
@@ -14,7 +14,8 @@
 
 #[cfg(feature="pkg-config")]
 fn build_pkgconfig() -> bool {
-    if pkg_config::find_library("sdl2").is_err() {
+    let opts = pkg_config::default_options("sdl2");
+    if pkg_config::find_library_opts("sdl2", &opts).is_err() {
         panic!("Could not find SDL2 via pkgconfig");
     }
     true
Use the new pkgconfig API
