diff --git a/gn/ar.py b/gn/ar.py
index dc3ae8d..c7ffb04 100644
--- a/gn/ar.py
+++ b/gn/ar.py
@@ -15,4 +15,16 @@
 
 if os.path.exists(output):
   os.remove(output)
-sys.exit(subprocess.call([ar, "rcs", output, "@" + rspfile]))
+
+if sys.platform != 'darwin':
+  sys.exit(subprocess.call([ar, "rcs", output, "@" + rspfile]))
+
+# Mac ar doesn't support @rspfile syntax.
+objects = open(rspfile).read().split()
+# It also spams stderr with warnings about objects having no symbols.
+pipe = subprocess.Popen([ar, "rcs", output] + objects, stderr=subprocess.PIPE)
+_, err = pipe.communicate()
+for line in err.splitlines():
+  if 'has no symbols' not in line:
+    sys.stderr.write(line + '\n')
+sys.exit(pipe.returncode)