diff --git a/build.zig b/build.zig
index 76534139d5739097e762e8898c962da392756604..94625483d352824f7b5bc9d1bbe43b2c123a12c0 100644
--- a/build.zig
+++ b/build.zig
@@ -769,6 +769,7 @@ const zig_cpp_sources = [_][]const u8{
     // These are planned to stay even when we are self-hosted.
     "src/zig_llvm.cpp",
     "src/zig_clang.cpp",
+    "src/zig_llvm-ar.cpp",
     "src/zig_clang_driver.cpp",
     "src/zig_clang_cc1_main.cpp",
     "src/zig_clang_cc1as_main.cpp",