test: modify the error tests for user error handler

It is not clear that after a MPI function calls the user error handler,
whether it should return MPI_SUCESS or not. Update the tests not to
assume the MPI will return the error code after invoking the error
handler.

Rationale: if user want the MPI function to return error code, they
should use MPI_ERRORS_RETURN instead. Otherwise, we assume the user
error handler "resolved" the error. User always can throw an exception
in their error handlers.

test/mpi/errors/f77/io/uerrhandf.f

@@ -47,14 +47,10 @@ program main
       call mpi_comm_set_errhandler( wdup, comm_errh, ierr )
       call mpi_comm_size( wdup, wdsize, ierr )
       call mpi_send( id, 1, MPI_INTEGER, wdsize, -37, wdup, ierr )
-      if (ierr .eq. MPI_SUCCESS) then
-         print *, ' Failed to detect error in use of MPI_SEND'
+C NOTE: ierr may be MPI_SUCCESS but handler should be invoked
+      if (iseen(1) .ne. 1) then
          errs = errs + 1
-      else
-         if (iseen(1) .ne. 1) then
-            errs = errs + 1
-            print *, ' Failed to increment comm error counter'
-         endif
+         print *, ' Failed to increment comm error counter'
       endif
 
       asize = 2*sizeofint
@@ -68,14 +64,10 @@ program main
       asize = 0
       call mpi_put( winbuf, 1, MPI_INT, wdsize, asize, 1, MPI_INT, winh,
      $     ierr )
-      if (ierr .eq. MPI_SUCCESS) then
-         print *, ' Failed to detect error in use of MPI_PUT'
+C NOTE: ierr may be MPI_SUCCESS but handler should be invoked
+      if (iseen(3) .ne. 1) then
          errs = errs + 1
-      else
-         if (iseen(3) .ne. 1) then
-            errs = errs + 1
-            print *, ' Failed to increment win error counter'
-         endif
+         print *, ' Failed to increment win error counter'
       endif
 
       call mpi_file_open( MPI_COMM_SELF, 'ftest', MPI_MODE_CREATE +
@@ -89,14 +81,10 @@ program main
       offset = -100
       call mpi_file_read_at( fh, offset, winbuf, 1, MPI_INTEGER, status,
      $     ierr )
-      if (ierr .eq. MPI_SUCCESS) then
-         print *, ' Failed to detect error in use of MPI_PUT'
+C NOTE: ierr may be MPI_SUCCESS but handler should be invoked
+      if (iseen(2) .ne. 1) then
          errs = errs + 1
-      else
-         if (iseen(2) .ne. 1) then
-            errs = errs + 1
-            print *, ' Failed to increment file error counter'
-         endif
+         print *, ' Failed to increment file error counter'
       endif
 
       call mpi_comm_free( wdup, ierr )

test/mpi/errors/session/comm_create_from_group.c

@@ -52,12 +52,9 @@ int main(int argc, char *argv[])
     }
 
     /* try to get a communicator with NULL comm as arg */
+    /* NOTE: the rc may be MPI_SUCCESS here but the errhandler should be invoked */
     rc = MPI_Comm_create_from_group(ghandle, "org.mpi-forum.mpi-v4_0.example-ex10_8",
                                     MPI_INFO_NULL, errhandler, NULL);
-    if (rc == MPI_SUCCESS) {
-        errs++;
-        goto fn_exit;
-    }
 
     /* get a communicator */
     rc = MPI_Comm_create_from_group(ghandle, "org.mpi-forum.mpi-v4_0.example-ex10_8",