diff --git a/src/bootstrap/native.rs b/src/bootstrap/native.rs
index 7bf9ea2688..4d53c2a7d4 100644
--- a/src/bootstrap/native.rs
+++ b/src/bootstrap/native.rs
@@ -293,6 +293,10 @@ impl Step for Llvm {
             cfg.define("PYTHON_EXECUTABLE", python);
         }
 
+        if let Some(ref libtool) = env::var_os("CMAKE_LIBTOOL") {
+            cfg.define("CMAKE_LIBTOOL", libtool);
+        }
+
         configure_cmake(builder, target, &mut cfg);
 
         // FIXME: we don't actually need to build all LLVM tools and all LLVM