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paddle/framework/op_desc.cc

@@ -200,6 +200,7 @@ static InferShapeFuncMap &InferShapeFuncs() {
     // all registered kernels
     for (auto &pair : OperatorWithKernel::AllOpKernels()) {
       auto &info = info_map.Get(pair.first);
+      // use empty type here to avoid runtime checks.
       auto op =
           static_cast<OperatorWithKernel *>(info.Creator()("", {}, {}, {}));
       g_map->insert(