Method TearDown

tests/test_expanded_tensor_ops.cpp:25–28

protected:
    void SetUp() override { cudaGetLastError(); }
    void TearDown() override {
        cudaError_t err = sync_and_check();
        EXPECT_EQ(err, cudaSuccess) << "Residual: " << cudaGetErrorString(err);
    }
};

// ===== Stack dim=2 correctness (the root cause bug) =====