diff --git a/src/bootstrap/native.rs b/src/bootstrap/native.rs
index cfd20b02aaf..ee0eca5d482 100644
--- a/src/bootstrap/native.rs
+++ b/src/bootstrap/native.rs
@@ -129,6 +129,15 @@ impl Step for Llvm {
            .define("LLVM_TARGET_ARCH", target.split('-').next().unwrap())
            .define("LLVM_DEFAULT_TARGET_TRIPLE", target);
 
+
+        // This setting makes the LLVM tools link to the dynamic LLVM library,
+        // which saves both memory during parallel links and overall disk space
+        // for the tools.  We don't distribute any of those tools, so this is
+        // just a local concern.  However, it doesn't work well everywhere.
+        if target.contains("linux-gnu") || target.contains("apple-darwin") {
+           cfg.define("LLVM_LINK_LLVM_DYLIB", "ON");
+        }
+
         if target.contains("msvc") {
             cfg.define("LLVM_USE_CRT_DEBUG", "MT");
             cfg.define("LLVM_USE_CRT_RELEASE", "MT");