diff --git a/src/comp/driver/rustc.rs b/src/comp/driver/rustc.rs
index 35e450244ac8..8e293e98f0d0 100644
--- a/src/comp/driver/rustc.rs
+++ b/src/comp/driver/rustc.rs
@@ -489,7 +489,7 @@ fn build_session_options(match: getopts::match)
     ret sopts;
 }
 
-fn build_session(sopts: @session::options) -> session::session {
+fn build_session(sopts: @session::options, input: str) -> session::session {
     let target_cfg = build_target_config(sopts);
     let cstore = cstore::mk_cstore();
     let filesearch = filesearch::mk_filesearch(
@@ -498,7 +498,7 @@ fn build_session(sopts: @session::options) -> session::session {
         sopts.addl_lib_search_paths);
     ret session::session(target_cfg, sopts, cstore,
                          @{cm: codemap::new_codemap(), mutable next_id: 1},
-                         none, 0u, filesearch, false);
+                         none, 0u, filesearch, false, fs::dirname(input));
 }
 
 fn parse_pretty(sess: session::session, &&name: str) -> pp_mode {
@@ -644,7 +644,7 @@ fn main(args: [str]) {
     };
 
     let sopts = build_session_options(match);
-    let sess = build_session(sopts);
+    let sess = build_session(sopts, ifile);
     let odir = getopts::opt_maybe_str(match, "out-dir");
     let ofile = getopts::opt_maybe_str(match, "o");
     let cfg = build_configuration(sess, binary, ifile);
@@ -676,7 +676,7 @@ mod test {
               ok(m) { m }
             };
         let sessopts = build_session_options(match);
-        let sess = build_session(sessopts);
+        let sess = build_session(sessopts, "");
         let cfg = build_configuration(sess, "whatever", "whatever");
         assert (attr::contains_name(cfg, "test"));
     }
@@ -690,7 +690,7 @@ mod test {
               ok(m) { m }
             };
         let sessopts = build_session_options(match);
-        let sess = build_session(sessopts);
+        let sess = build_session(sessopts, "");
         let cfg = build_configuration(sess, "whatever", "whatever");
         let test_items = attr::find_meta_items_by_name(cfg, "test");
         assert (vec::len(test_items) == 1u);
diff --git a/src/comp/driver/session.rs b/src/comp/driver/session.rs
index 6645d5d68946..1bedbf87f7ea 100644
--- a/src/comp/driver/session.rs
+++ b/src/comp/driver/session.rs
@@ -60,7 +60,8 @@ obj session(targ_cfg: @config,
             mutable main_fn: option::t<node_id>,
             mutable err_count: uint,
             filesearch: filesearch::filesearch,
-            mutable building_library: bool) {
+            mutable building_library: bool,
+            working_dir: str) {
     fn get_targ_cfg() -> @config { ret targ_cfg; }
     fn get_opts() -> @options { ret opts; }
     fn get_cstore() -> metadata::cstore::cstore { cstore }
@@ -123,6 +124,9 @@ obj session(targ_cfg: @config,
     fn set_building_library(crate: @ast::crate) {
         building_library = session::building_library(opts.crate_type, crate);
     }
+    fn get_working_dir() -> str {
+        ret working_dir;
+    }
 }
 
 fn building_library(req_crate_type: crate_type, crate: @ast::crate) -> bool {
diff --git a/src/comp/middle/debuginfo.rs b/src/comp/middle/debuginfo.rs
index 7460244d479e..c11f65dc34f1 100644
--- a/src/comp/middle/debuginfo.rs
+++ b/src/comp/middle/debuginfo.rs
@@ -162,13 +162,18 @@ fn create_compile_unit(cx: @crate_ctxt, full_path: str)
       option::none. {}
     }
 
-    let fname = fs::basename(full_path);
-    let path = fs::dirname(full_path);
+    let work_dir = cx.sess.get_working_dir();
+    let file_path = if str::starts_with(full_path, work_dir) {
+        str::slice(full_path, str::byte_len(work_dir),
+                   str::byte_len(full_path))
+    } else {
+        full_path
+    };
     let unit_metadata = [lltag(tg),
                          llunused(),
                          lli32(DW_LANG_RUST),
-                         llstr(fname),
-                         llstr(path),
+                         llstr(file_path),
+                         llstr(work_dir),
                          llstr(#env["CFG_VERSION"]),
                          lli1(false), // main compile unit
                          lli1(cx.sess.get_opts().optimize != 0u),