diff --git a/llvm/utils/gn/build/BUILD.gn b/llvm/utils/gn/build/BUILD.gn
--- a/llvm/utils/gn/build/BUILD.gn
+++ b/llvm/utils/gn/build/BUILD.gn
@@ -221,6 +221,7 @@
     "-fPIC",
     "-funwind-tables",
     "-gline-tables-only",
+    "-fvisibility=hidden",
   ]
 }