diff --git a/lib/internal/cluster/master.js b/lib/internal/cluster/master.js
index 9bdb0181d3db93..70707e359f4997 100644
--- a/lib/internal/cluster/master.js
+++ b/lib/internal/cluster/master.js
@@ -67,7 +67,7 @@ cluster.setupMaster = function(options) {
   // process has its own memory mappings.)
   if (settings.execArgv.some((s) => s.startsWith('--prof')) &&
       !settings.execArgv.some((s) => s.startsWith('--logfile='))) {
-    settings.execArgv = settings.execArgv.concat(['--logfile=v8-%p.log']);
+    settings.execArgv = [...settings.execArgv, '--logfile=v8-%p.log'];
   }
 
   cluster.settings = settings;
@@ -104,7 +104,7 @@ function setupSettingsNT(settings) {
 
 function createWorkerProcess(id, env) {
   const workerEnv = { ...process.env, ...env, NODE_UNIQUE_ID: `${id}` };
-  const execArgv = cluster.settings.execArgv.slice();
+  const execArgv = [...cluster.settings.execArgv];
   const debugArgRegex = /--inspect(?:-brk|-port)?|--debug-port/;
   const nodeOptions = process.env.NODE_OPTIONS ?
     process.env.NODE_OPTIONS : '';