diff --git a/bench/nanobench.cpp b/bench/nanobench.cpp
index 887fab3bad..c2afca65cb 100644
--- a/bench/nanobench.cpp
+++ b/bench/nanobench.cpp
@@ -1361,7 +1361,7 @@ int nanobench_main() {
     return 0;
 }
 
-#if !defined SK_BUILD_FOR_IOS
+#if !defined(SK_BUILD_FOR_IOS) || defined(NANOBENCH_DEFINE_MAIN)
 int main(int argc, char** argv) {
     SkCommandLineFlags::Parse(argc, argv);
     return nanobench_main();
diff --git a/gn/BUILD.gn b/gn/BUILD.gn
index 11ab560a2e..cd7f8f74cf 100644
--- a/gn/BUILD.gn
+++ b/gn/BUILD.gn
@@ -212,7 +212,7 @@ config("default") {
     # our clever hack to give each tool back its own main().
     cflags += [
       "-DDM_DEFINE_MAIN",
-      "-Dnanobench_main=main",
+      "-DNANOBENCH_DEFINE_MAIN",
       "-Dtool_main=main",
       "-Dtest_main=main",
     ]