diff --git a/src/ast/converters/converter.h b/src/ast/converters/converter.h
index 05ba1eb08..facff786e 100644
--- a/src/ast/converters/converter.h
+++ b/src/ast/converters/converter.h
@@ -25,7 +25,6 @@ Notes:
 class converter {
     unsigned m_ref_count = 0;
 public:
-    converter() = default;
     virtual ~converter() = default;
 
     void inc_ref() { ++m_ref_count;  }
diff --git a/src/ast/pattern/pattern_inference.h b/src/ast/pattern/pattern_inference.h
index d548acf3b..6ea9777a1 100644
--- a/src/ast/pattern/pattern_inference.h
+++ b/src/ast/pattern/pattern_inference.h
@@ -50,8 +50,6 @@ class smaller_pattern {
 
 public:
 
-    smaller_pattern() = default;
-
     smaller_pattern & operator=(smaller_pattern const &) = delete;
 
     bool operator()(unsigned num_bindings, expr * p1, expr * p2);