diff --git a/cpp/src/scheduler/task/SearchTask.cpp b/cpp/src/scheduler/task/SearchTask.cpp
index 20cd736538b50fede9d2482f73d1d13bb0ed36ce..1a3bda05c39fc1376ccc6a9e45c30950c0b185a2 100644
--- a/cpp/src/scheduler/task/SearchTask.cpp
+++ b/cpp/src/scheduler/task/SearchTask.cpp
@@ -163,10 +163,10 @@ XSearchTask::Execute() {
     std::vector<float> output_distance;
     for (auto &context : search_contexts_) {
         //step 1: allocate memory
-        auto nq = context->nq();
-        auto topk = context->topk();
-        auto nprobe = context->nprobe();
-        auto vectors = context->vectors();
+        uint64_t nq = context->nq();
+        uint64_t topk = context->topk();
+        uint64_t nprobe = context->nprobe();
+        const float* vectors = context->vectors();
 
         output_ids.resize(topk * nq);
         output_distance.resize(topk * nq);