1 files changed, 2 insertions, 2 deletions
diff --git a/src/theory/arith/delta_rational.h b/src/theory/arith/delta_rational.h
index 60db60c1a..78d5fb665 100644
--- a/src/theory/arith/delta_rational.h
+++ b/src/theory/arith/delta_rational.h
@@ -60,7 +60,7 @@ public:
     return DeltaRational(tmpC, tmpK);
   }
 
-  DeltaRational operator*(CVC4::Rational& a) const{
+  DeltaRational operator*(const Rational& a) const{
     CVC4::Rational tmpC = a*c;
     CVC4::Rational tmpK = a*k;
     return DeltaRational(tmpC, tmpK);
@@ -95,7 +95,7 @@ public:
     return *(this);
   }
 
-  DeltaRational& operator*=(CVC4::Rational& a){
+  DeltaRational& operator*=(const CVC4::Rational& a){
     c = c * a;
     k = k * a;