diff --git a/src/ast/fpa_decl_plugin.cpp b/src/ast/fpa_decl_plugin.cpp
index 419175a7f..c0caaa3ca 100644
--- a/src/ast/fpa_decl_plugin.cpp
+++ b/src/ast/fpa_decl_plugin.cpp
@@ -160,7 +160,7 @@ bool fpa_decl_plugin::is_rm_numeral(expr * n, mpf_rounding_mode & val) {
         return true;
     }
 
-    return 0;
+    return false;
 }
 
 bool fpa_decl_plugin::is_rm_numeral(expr * n) {
diff --git a/src/util/hashtable.h b/src/util/hashtable.h
index 0421fd300..742438814 100644
--- a/src/util/hashtable.h
+++ b/src/util/hashtable.h
@@ -449,7 +449,7 @@ public:
             INSERT_LOOP_CORE_BODY();
         }
         UNREACHABLE();
-        return 0;
+        return false;
     }
 
     bool insert_if_not_there_core(const data & e, entry * & et) {