diff --git a/src/ML-PACE/pair_pace.h b/src/ML-PACE/pair_pace.h
index 9b5d2c5480..5cff7045fa 100644
--- a/src/ML-PACE/pair_pace.h
+++ b/src/ML-PACE/pair_pace.h
@@ -52,7 +52,7 @@ class PairPACE : public Pair {
 
  protected:
   struct ACEImpl *aceimpl;
-  int nmax_corerep = 0;
+  int nmax_corerep;
 
   virtual void allocate();
   double *corerep_factor;                    //per-atom core-rep factor (= 1 - fcut)
diff --git a/src/ML-PACE/pair_pace_extrapolation.h b/src/ML-PACE/pair_pace_extrapolation.h
index 440d999029..e01fdd2329 100644
--- a/src/ML-PACE/pair_pace_extrapolation.h
+++ b/src/ML-PACE/pair_pace_extrapolation.h
@@ -46,15 +46,15 @@ class PairPACEExtrapolation : public Pair {
 
  protected:
   struct ACEALImpl *aceimpl;
-  int nmax = 0, nmax_corerep = 0;
+  int nmax, nmax_corerep;
 
   virtual void allocate();
   std::vector<std::string> element_names;    // list of elements (used by dump pace/extrapolation)
-  double *extrapolation_grade_gamma = nullptr;         //per-atom gamma value
-  double *corerep_factor = nullptr;                    //per-atom core-rep factor (= 1 - fcut)
+  double *extrapolation_grade_gamma;         //per-atom gamma value
+  double *corerep_factor;                    //per-atom core-rep factor (= 1 - fcut)
 
-  int flag_compute_extrapolation_grade = 0;
-  int flag_corerep_factor = 0;
+  int flag_compute_extrapolation_grade;
+  int flag_corerep_factor;
 
   double **scale;