diff --git a/include/valijson/constraints/concrete_constraints.hpp b/include/valijson/constraints/concrete_constraints.hpp
index 6cc0853..6b3b7e0 100644
--- a/include/valijson/constraints/concrete_constraints.hpp
+++ b/include/valijson/constraints/concrete_constraints.hpp
@@ -441,7 +441,7 @@ public:
     }
 
 private:
-    uint64_t maxItems;
+    size_t maxItems;
 };
 
 /**
@@ -495,7 +495,7 @@ public:
     }
 
 private:
-    uint64_t maxProperties;
+    size_t maxProperties;
 };
 
 /**
@@ -562,7 +562,7 @@ public:
     }
 
 private:
-    uint64_t minItems;
+    size_t minItems;
 };
 
 /**
@@ -616,7 +616,7 @@ public:
     }
 
 private:
-    uint64_t minProperties;
+    size_t minProperties;
 };
 
 /**
diff --git a/include/valijson/schema.hpp b/include/valijson/schema.hpp
index be60e2f..2308e36 100644
--- a/include/valijson/schema.hpp
+++ b/include/valijson/schema.hpp
@@ -46,7 +46,7 @@ public:
     virtual ~Schema()
     {
         sharedEmptySubschema->~Subschema();
-        freeFn((void*)(sharedEmptySubschema));
+        freeFn(const_cast<Subschema *>(sharedEmptySubschema));
         sharedEmptySubschema = NULL;
 
         try {
diff --git a/include/valijson/schema_parser.hpp b/include/valijson/schema_parser.hpp
index 3e7f6bc..0c19014 100644
--- a/include/valijson/schema_parser.hpp
+++ b/include/valijson/schema_parser.hpp
@@ -444,7 +444,7 @@ private:
         Schema &rootSchema,
         const std::string &jsonRef,
         const AdapterType &rootNode,
-        const AdapterType &node,
+        const AdapterType &,
         const Subschema &subschema,
         const boost::optional<std::string> currentScope,
         const std::string &nodePath,
diff --git a/include/valijson/subschema.hpp b/include/valijson/subschema.hpp
index a694a49..a6510ab 100644
--- a/include/valijson/subschema.hpp
+++ b/include/valijson/subschema.hpp
@@ -66,9 +66,9 @@ public:
         try {
             for (std::vector<const Constraint *>::iterator itr =
                     constraints.begin(); itr != constraints.end(); ++itr) {
-                const Constraint *constraint = *itr;
+                Constraint *constraint = const_cast<Constraint *>(*itr);
                 constraint->~Constraint();
-                freeFn((void*)(constraint));
+                freeFn(constraint);
             }
             constraints.clear();
         } catch (const std::exception &e) {
diff --git a/include/valijson/validation_visitor.hpp b/include/valijson/validation_visitor.hpp
index e4be02a..9c1964c 100644
--- a/include/valijson/validation_visitor.hpp
+++ b/include/valijson/validation_visitor.hpp
@@ -1026,7 +1026,7 @@ public:
      *
      * @return  true if validation succeeds, false otherwise
      */
-    virtual bool visit(const UniqueItemsConstraint &constraint)
+    virtual bool visit(const UniqueItemsConstraint &)
     {
         if ((strictTypes && !target.isArray()) || !target.maybeArray()) {
             return true;