modify export air and check file_name

mindspore/_checkparam.py

@@ -429,8 +429,9 @@ class Validator:
 
     @staticmethod
     def check_file_name_by_regular(target, reg=None, flag=re.ASCII, prim_name=None):
+        """Check whether file name is legitimate."""
         if reg is None:
-            reg = r"^[0-9a-zA-Z\_\-\.\/\\]*$"
+            reg = r"^[0-9a-zA-Z\_\-\.\/\\]+$"
         if re.match(reg, target, flag) is None:
             prim_name = f'in `{prim_name}`' if prim_name else ""
             raise ValueError("'{}' {} is illegal, it should be match regular'{}' by flags'{}'".format(

mindspore/ccsrc/transform/graph_ir/convert.cc

@@ -596,8 +596,10 @@ void DfGraphConvertor::TraceOutput(const AnfNodePtr node) {
   // Trace value node
   if (node->isa<ValueNode>()) {
     auto op = Convert(anf_out);
-    graph_outputs_.emplace_back(std::make_pair(*op, ""));
-    AddGraphConstInput(op);
+    if (op != nullptr) {
+      graph_outputs_.emplace_back(std::make_pair(*op, ""));
+      AddGraphConstInput(op);
+    }
     return;
   }