more warnings in place of assertions

src/workload/methods/codes-darshan3-io-wrkld.c

@@ -271,14 +271,32 @@ static int darshan_psx_io_workload_load(const char *params, int app_id, int rank
                 dur_cur->mpiio_file_rec = *mpiio_file_rec;
                 break;
             }
+
+            if((dur_cur->psx_file_rec.base_rec.id == mpiio_file_rec->base_rec.id)
+                && (dur_cur->psx_file_rec.base_rec.rank == -1)
+                && (mpiio_file_rec->base_rec.rank != -1))
+            {
+                fprintf(stderr, "WARNING: id %" PRIu64 " has non-shared MPI record and shared POSIX record.  Skipping POSIX record which may have been generated by stat() calls.\n", mpiio_file_rec->base_rec.id);
+
+                dur_cur->psx_file_rec.counters[POSIX_OPENS] = 0;
+            }
+                
         }
-        /* if we exit loop with null dur_cur, that means that an mpiio record is present
+        
+        /* if we fall through to here, that means that an mpiio record is present
          * for which there is no exact match in the posix records.  This
          * could (for example) happen if mpiio was using deferred opens,
          * producing a shared record in mpi and unique records in posix.  Or
-         * if mpiio is using a non-posix back end
+         * if mpiio is using a non-posix back end. Or if we skip the posix
+         * records because the app issued a stat() on every rank but only
+         * did I/O on a subset.
          */
-        assert(dur_cur);
+        dur_new = calloc(1, sizeof(*dur_new));
+        assert(dur_new);
+
+        dur_new->mpiio_file_rec = *mpiio_file_rec;
+        dur_new->next = dur_head;
+        dur_head = dur_new;
     }
 
     /* file records have all been retrieved from darshan log.  Now we loop
@@ -744,7 +762,8 @@ static void generate_psx_file_events(
     if(file->base_rec.rank == -1)
         meta_op_time /= total_rank_cnt;
 
-    assert(meta_op_time >= 0);
+    if(meta_op_time < 0)
+        meta_op_time = DARSHAN_NEGLIGIBLE_DELAY;
 
     /* set the create flag if the file was written to */
     if (file->counters[POSIX_BYTES_WRITTEN])
@@ -1259,6 +1278,15 @@ static void psx_calc_io_delays(
         *inter_io_delay = 0;
         return;
     }
+    
+    if(num_io_ops == 0)
+    {
+        *first_io_delay = 0;
+        *close_delay = 0;
+        *inter_io_delay = 0;
+        fprintf(stderr, "WARNING: id %" PRIu64 " has unaccounted total_delay, possibly stat() calls that are not supported by generator.\n", file->base_rec.id);
+        return;
+    }
 
     /* determine the start time of the first io operation */
     first_io_time = MIN(