add random seed initialization and broadcasting for tests with MPIsimplify OpenMP linking logic

Author: allnes

cmake/openmp.cmake

@@ -20,24 +20,6 @@ endfunction()
 
 function(ppc_link_openmp exec_func_lib)
   find_package(OpenMP REQUIRED)
-  # Link the canonical imported target if available
-  if(TARGET OpenMP::OpenMP_CXX)
-    target_link_libraries(${exec_func_lib} PUBLIC OpenMP::OpenMP_CXX)
-  endif()
-
-  if(APPLE)
-    # Homebrew libomp common paths
-    find_path(LIBOMP_INCLUDE_DIR omp.h HINTS /opt/homebrew/opt/libomp/include
-                                             /usr/local/opt/libomp/include)
-    find_library(LIBOMP_LIBRARY omp HINTS /opt/homebrew/opt/libomp/lib
-                                          /usr/local/opt/libomp/lib)
-    if(LIBOMP_INCLUDE_DIR)
-      target_include_directories(${exec_func_lib} PUBLIC ${LIBOMP_INCLUDE_DIR})
-    endif()
-    if(LIBOMP_LIBRARY)
-      target_link_libraries(${exec_func_lib} PUBLIC ${LIBOMP_LIBRARY})
-      # Ensure Clang generates OpenMP code
-      target_compile_options(${exec_func_lib} PUBLIC -Xclang -fopenmp)
-    endif()
-  endif()
+  target_link_libraries(${exec_func_lib} PUBLIC ${OpenMP_libomp_LIBRARY}
+                                                OpenMP::OpenMP_CXX)
 endfunction()

modules/runners/src/runners.cpp

@@ -3,10 +3,14 @@
 #include <gtest/gtest.h>
 #include <mpi.h>
 
+#include <chrono>
+#include <cstdint>
 #include <cstdlib>
+#include <ctime>
 #include <format>
 #include <iostream>
 #include <memory>
+#include <random>
 #include <stdexcept>
 #include <string>
 
@@ -87,6 +91,24 @@ int Init(int argc, char **argv) {
   tbb::global_control control(tbb::global_control::max_allowed_parallelism, ppc::util::GetNumThreads());
 
   ::testing::InitGoogleTest(&argc, argv);
+  unsigned int seed = 0;
+  int rank_for_seed = -1;
+  MPI_Comm_rank(MPI_COMM_WORLD, &rank_for_seed);
+
+  if (rank_for_seed == 0) {
+    try {
+      seed = std::random_device{}();
+    } catch (...) {
+      seed = 0;
+    }
+    if (seed == 0) {
+      const auto now = static_cast<std::uint64_t>(std::chrono::steady_clock::now().time_since_epoch().count());
+      seed = static_cast<unsigned int>(((now & 0x7fffffffULL) | 1ULL));
+    }
+  }
+
+  MPI_Bcast(&seed, 1, MPI_UNSIGNED, 0, MPI_COMM_WORLD);
+  ::testing::GTEST_FLAG(random_seed) = static_cast<int>(seed);
 
   auto &listeners = ::testing::UnitTest::GetInstance()->listeners();
   int rank = -1;