Fixed bug with MPI_FINALIZE when it was called by PETSc earlier

Common/GmshMessage.cpp

@@ -185,6 +185,9 @@ void Msg::Exit(int level)
 #if defined(HAVE_MPI)
     // force general abort (wven if the fatal error occurred on 1 cpu only)
     MPI_Abort(MPI_COMM_WORLD, level);
+    int finalized;
+    MPI_Finalized(&finalized);
+    if (!finalized)
       MPI_Finalize();
 #endif
     FinalizeOnelab();
@@ -215,6 +218,9 @@ void Msg::Exit(int level)
   PetscFinalize();
 #endif
 #if defined(HAVE_MPI)
+  int finalized; //Some PETSc versions call MPI_FINALIZE
+  MPI_Finalized(&finalized);
+  if (!finalized)
     MPI_Finalize();
 #endif
   FinalizeOnelab();