diff --git a/src/sat/smt/xor_solver.cpp b/src/sat/smt/xor_solver.cpp
index 27354eac2..941cd21d4 100644
--- a/src/sat/smt/xor_solver.cpp
+++ b/src/sat/smt/xor_solver.cpp
@@ -37,7 +37,7 @@ namespace xr {
     }
     
     void solver::get_antecedents(sat::literal l, sat::ext_justification_idx idx,
-                                 sat::literal_vector & r, bool probing) {
+                                 sat::literal_vector & r, bool probing, sat::proof_hint*& ph) {
         
     }
     
diff --git a/src/sat/smt/xor_solver.h b/src/sat/smt/xor_solver.h
index 3da30c580..0748e1e9b 100644
--- a/src/sat/smt/xor_solver.h
+++ b/src/sat/smt/xor_solver.h
@@ -30,7 +30,7 @@ namespace xr {
 
         void asserted(sat::literal l) override;
         bool unit_propagate() override;
-        void get_antecedents(sat::literal l, sat::ext_justification_idx idx, sat::literal_vector & r, bool probing) override;
+        void get_antecedents(sat::literal l, sat::ext_justification_idx idx, sat::literal_vector & r, bool probing, sat::proof_hint*& ph) override;
 
         void pre_simplify() override;
         void simplify() override;