Try adding a src file to platform constraint tests to see if that fixes macos

Author: jkurland-roku

tests/BUILD.bazel

@@ -176,6 +176,7 @@ cc_library(
 cc_test(
     name = "test_cxx_standard_is_17",
     size = "small",
+    srcs = ["test_cxx_standard_main.cc"],
     args = ["201703"],
     deps = [":test_cxx_standard_lib"],
 )
@@ -189,6 +190,7 @@ transition_library_to_platform(
 cc_test(
     name = "test_cxx_standard_is_20",
     size = "small",
+    srcs = ["test_cxx_standard_main.cc"],
     args = ["202002"],
     deps = [":test_cxx_standard_lib_transitioned"],
 )

tests/test_cxx_standard.cc

@@ -1,7 +1,7 @@
 #include <iostream>
 #include <cstdlib>
 
-int main(int argc, char** argv) {
+int run_test(int argc, char** argv) {
     if (argc != 2) {
         std::cout << "Not enough arguments" << std::endl;
         return 1;
@@ -19,4 +19,4 @@ int main(int argc, char** argv) {
         return 1;
     }
     return 0;
-}
+}

tests/test_cxx_standard_main.cc

@@ -0,0 +1,5 @@
+int run_test(int argc, char** argv);
+
+int main(int argc, char** argv) {
+    return run_test(argc, argv);
+}