diff --git a/include/rapidjson/document.h b/include/rapidjson/document.h
index 0b123ae..1dad630 100644
--- a/include/rapidjson/document.h
+++ b/include/rapidjson/document.h
@@ -1083,6 +1083,7 @@ public:
      */
     template <typename T> RAPIDJSON_DISABLEIF_RETURN((internal::IsGenericValue<T>), (bool)) operator!=(const T& rhs) const { return !(*this == rhs); }
 
+#ifndef __cpp_lib_three_way_comparison
     //! Equal-to operator with arbitrary types (symmetric version)
     /*! \return (rhs == lhs)
      */
@@ -1093,6 +1094,7 @@ public:
      */
     template <typename T> friend RAPIDJSON_DISABLEIF_RETURN((internal::IsGenericValue<T>), (bool)) operator!=(const T& lhs, const GenericValue& rhs) { return !(rhs == lhs); }
     //@}
+#endif
 
     //!@name Type
     //@{
diff --git a/include/rapidjson/schema.h b/include/rapidjson/schema.h
index 9e99bf5..a6cbfed 100644
--- a/include/rapidjson/schema.h
+++ b/include/rapidjson/schema.h
@@ -530,12 +530,12 @@ public:
             AssignIfExist(allOf_, *schemaDocument, p, value, GetAllOfString(), document);
             AssignIfExist(anyOf_, *schemaDocument, p, value, GetAnyOfString(), document);
             AssignIfExist(oneOf_, *schemaDocument, p, value, GetOneOfString(), document);
-        }
 
-        if (const ValueType* v = GetMember(value, GetNotString())) {
-            schemaDocument->CreateSchema(&not_, p.Append(GetNotString(), allocator_), *v, document, id_);
-            notValidatorIndex_ = validatorCount_;
-            validatorCount_++;
+            if (const ValueType* v = GetMember(value, GetNotString())) {
+                schemaDocument->CreateSchema(&not_, p.Append(GetNotString(), allocator_), *v, document, id_);
+                notValidatorIndex_ = validatorCount_;
+                validatorCount_++;
+            }
         }
 
         // Object
@@ -983,7 +983,7 @@ public:
         }
 
         if (additionalPropertiesSchema_) {
-            if (additionalPropertiesSchema_ && context.patternPropertiesSchemaCount > 0) {
+            if (context.patternPropertiesSchemaCount > 0) {
                 context.patternPropertiesSchemas[context.patternPropertiesSchemaCount++] = additionalPropertiesSchema_;
                 context.valueSchema = typeless_;
                 context.valuePatternValidatorType = Context::kPatternValidatorWithAdditionalProperty;