diff --git a/source/module_hsolver/diago_cusolvermp.h b/source/module_hsolver/diago_cusolvermp.h
index a8d1a38002..4a5039cd2b 100644
--- a/source/module_hsolver/diago_cusolvermp.h
+++ b/source/module_hsolver/diago_cusolvermp.h
@@ -8,7 +8,7 @@
 #include "module_hsolver/kernels/cuda/diag_cusolvermp.cuh"
 namespace hsolver
 {
-// DiagoCusolverMP class, derived from DiagH, for diagonalization using CUSOLVERMP
+// DiagoCusolverMP class, for diagonalization using CUSOLVERMP
 template <typename T>
 class DiagoCusolverMP
 {
diff --git a/source/module_hsolver/diago_pexsi.h b/source/module_hsolver/diago_pexsi.h
index 657471a9e5..6ef9787ab2 100644
--- a/source/module_hsolver/diago_pexsi.h
+++ b/source/module_hsolver/diago_pexsi.h
@@ -12,7 +12,7 @@ namespace hsolver
 {
 
 template <typename T>
-class DiagoPexsi : public DiagH<T>
+class DiagoPexsi
 {
   private:
     using Real = typename GetTypeReal<T>::type;
@@ -20,7 +20,7 @@ class DiagoPexsi : public DiagH<T>
 
   public:
     DiagoPexsi(const Parallel_Orbitals* ParaV_in);
-    void diag(hamilt::Hamilt<T>* phm_in, psi::Psi<T>& psi, Real* eigenvalue_in) override;
+    void diag(hamilt::Hamilt<T>* phm_in, psi::Psi<T>& psi, Real* eigenvalue_in);
     const Parallel_Orbitals* ParaV;
     std::vector<T*> DM;
     std::vector<T*> EDM;