rustc: Don't rpath to librustrt.dylib

This library no longer exists, there's no reason for this rpath to exist any
more.

Author: alexcrichton

src/librustc/back/rpath.rs

@@ -42,25 +42,16 @@ pub fn get_rpath_flags(sess: &Session, out_filename: &Path) -> Vec<~str> {
     let sysroot = sess.filesearch().sysroot;
     let output = out_filename;
     let libs = sess.cstore.get_used_crates(cstore::RequireDynamic);
-    let libs = libs.move_iter().filter_map(|(_, l)| l.map(|p| p.clone())).collect();
-    // We don't currently rpath extern libraries, but we know
-    // where rustrt is and we know every rust program needs it
-    let libs = slice::append_one(libs, get_sysroot_absolute_rt_lib(sess));
+    let libs = libs.move_iter().filter_map(|(_, l)| {
+        l.map(|p| p.clone())
+    }).collect::<~[_]>();
 
     let rpaths = get_rpaths(os, sysroot, output, libs,
                             sess.opts.target_triple);
     flags.push_all(rpaths_to_flags(rpaths.as_slice()).as_slice());
     flags
 }
 
-fn get_sysroot_absolute_rt_lib(sess: &Session) -> Path {
-    let sysroot = sess.filesearch().sysroot;
-    let r = filesearch::relative_target_lib_path(sysroot, sess.opts.target_triple);
-    let mut p = sysroot.join(&r);
-    p.push(os::dll_filename("rustrt"));
-    p
-}
-
 pub fn rpaths_to_flags(rpaths: &[~str]) -> Vec<~str> {
     let mut ret = Vec::new();
     for rpath in rpaths.iter() {