diff --git a/BUILD.bazel b/BUILD.bazel
index 48102f11f..66af44b01 100644
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -18,7 +18,7 @@ cc_binary(
         "//tools/config:osx": [],
     }),
     copts = [
-        "-std=gnu99",
+        "-D_DEFAULT_SOURCE",
         "-DAUDIO",
         "-DGAMES",
         "-DHAVE_WIDECHAR",