upgrading to google benchmark v1.5.1; modifying benchmark_1.5.1/googletest/googletest/src/gtest_main.cc for MPI

Author: syclik

lib/benchmark_1.5.1/googletest/googletest/src/gtest_main.cc

@@ -29,6 +29,7 @@
 
 #include <cstdio>
 #include "gtest/gtest.h"
+#include <stan/math/prim/functor/mpi_cluster.hpp>
 
 #if GTEST_OS_ESP8266 || GTEST_OS_ESP32
 #if GTEST_OS_ESP8266
@@ -47,6 +48,16 @@ void loop() { RUN_ALL_TESTS(); }
 #else
 
 GTEST_API_ int main(int argc, char **argv) {
+
+#ifdef STAN_MPI
+  // for MPI testing we test with all workers in listen mode.
+  // No output is generated from the workers.
+  stan::math::mpi_cluster cluster;
+  cluster.listen();
+  if (cluster.rank_ != 0)
+    return 0;
+#endif
+
   printf("Running main() from %s\n", __FILE__);
   testing::InitGoogleTest(&argc, argv);
   return RUN_ALL_TESTS();