diff --git a/Cargo.lock b/Cargo.lock
index 4f044dcb65b..aeca3ecf472 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -19,7 +19,7 @@ dependencies = [
 [[package]]
 name = "ar"
 version = "0.6.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
+source = "git+https://github.com/mdsteele/rust-ar.git#1cfa68dcecaa063510758e8bdced7115a3393616"
 dependencies = [
  "byteorder 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -582,7 +582,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 name = "rustc_codegen_cranelift"
 version = "0.1.0"
 dependencies = [
- "ar 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ar 0.6.2 (git+https://github.com/mdsteele/rust-ar.git)",
  "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "cranelift 0.30.0 (git+https://github.com/CraneStation/cranelift.git)",
@@ -843,7 +843,7 @@ dependencies = [
 [metadata]
 "checksum aho-corasick 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "e6f484ae0c99fec2e858eb6134949117399f222608d84cadb3f58c1f97c2364c"
 "checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
-"checksum ar 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "579681b3fecd1e9d6b5ce6969e05f9feb913f296eddaf595be1166a5ca597bc4"
+"checksum ar 0.6.2 (git+https://github.com/mdsteele/rust-ar.git)" = "<none>"
 "checksum arrayvec 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)" = "92c7fb76bc8826a8b33b4ee5bb07a247a81e76764ab4d55e8f73e3a4d8808c71"
 "checksum atty 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "9a7d5b8723950951411ee34d271d99dddcc2035a16ab25310ea2c8cfd4369652"
 "checksum autocfg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a6d640bee2da49f60a4068a7fae53acde8982514ab7bae8b8cea9e88cbcfd799"
diff --git a/Cargo.toml b/Cargo.toml
index 14e05f70621..b71ad7ffb25 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -38,5 +38,8 @@ indexmap = "1.0.2"
 #[patch."https://github.com/gimli-rs/gimli.git"]
 #gimli = { path = "../" }
 
+[patch.crates-io]
+ar = { git = "https://github.com/mdsteele/rust-ar.git" }
+
 [profile.dev.overrides."*"]
 opt-level = 3
diff --git a/src/archive.rs b/src/archive.rs
index fb17bc88441..02b8c4fd14e 100644
--- a/src/archive.rs
+++ b/src/archive.rs
@@ -8,12 +8,14 @@ use rustc_codegen_ssa::{METADATA_FILENAME, RLIB_BYTECODE_EXTENSION};
 use rustc_codegen_ssa::back::archive::{ArchiveBuilder, find_library};
 
 struct ArchiveConfig<'a> {
-    pub sess: &'a Session,
-    pub dst: PathBuf,
-    pub src: Option<PathBuf>,
-    pub lib_search_paths: Vec<PathBuf>,
+    sess: &'a Session,
+    dst: PathBuf,
+    src: Option<PathBuf>,
+    lib_search_paths: Vec<PathBuf>,
+    is_like_osx: bool,
 }
 
+#[derive(Debug)]
 enum ArchiveEntry {
     FromArchive { archive_index: usize, entry_index: usize },
     File(File),
@@ -34,6 +36,7 @@ impl<'a> ArchiveBuilder<'a> for ArArchiveBuilder<'a> {
             dst: output.to_path_buf(),
             src: input.map(|p| p.to_path_buf()),
             lib_search_paths: archive_search_paths(sess),
+            is_like_osx: sess.target.target.options.is_like_osx,
         };
 
         let (src_archives, entries) = if let Some(src) = &config.src {
@@ -119,7 +122,23 @@ impl<'a> ArchiveBuilder<'a> for ArArchiveBuilder<'a> {
     }
 
     fn build(mut self) {
-        let mut builder = ar::Builder::new(File::create(&self.config.dst).unwrap());
+        println!("{:?}", self.src_archives.len());
+        println!("{:?}", self.entries);
+
+        enum BuilderKind {
+            Bsd(ar::Builder<File>),
+            Gnu(ar::GnuBuilder<File>),
+        }
+
+        let archive_file = File::create(&self.config.dst).unwrap();
+        let mut builder = if self.config.is_like_osx {
+            BuilderKind::Bsd(ar::Builder::new(archive_file))
+        } else {
+            BuilderKind::Gnu(ar::GnuBuilder::new(
+                archive_file,
+                self.entries.keys().map(|key| key.as_bytes().to_vec()).collect(),
+            ))
+        };
 
         // Add all files
         for (entry_name, entry) in self.entries.into_iter() {
@@ -133,10 +152,16 @@ impl<'a> ArchiveBuilder<'a> for ArArchiveBuilder<'a> {
                     header.set_uid(orig_header.uid());
                     header.set_gid(orig_header.gid());
                     header.set_mode(orig_header.mode());
-                    builder.append(&header, entry).unwrap();
+                    match builder {
+                        BuilderKind::Bsd(ref mut builder) => builder.append(&header, entry).unwrap(),
+                        BuilderKind::Gnu(ref mut builder) => builder.append(&header, entry).unwrap(),
+                    }
                 }
                 ArchiveEntry::File(mut file) => {
-                    builder.append_file(entry_name.as_bytes(), &mut file).unwrap();
+                    match builder {
+                        BuilderKind::Bsd(ref mut builder) => builder.append_file(entry_name.as_bytes(), &mut file).unwrap(),
+                        BuilderKind::Gnu(ref mut builder) => builder.append_file(entry_name.as_bytes(), &mut file).unwrap(),
+                    }
                 }
             }
         }