---
slug: "iOSアプリのビルド時duplicatesymbol_OBJC_CLASS_が大量に出て焦った時"
title: "When Duplicate Symbol _OBJC_CLASS_ Appears in Large Numbers During iOS App Build"
description: "\n\nWhen encountering a large number of duplicate symbol _OBJC_CLASS_ errors during an iOS app build"
url: "https://www.ytyng.com/en/blog/iOSアプリのビルド時duplicatesymbol_OBJC_CLASS_が大量に出て焦った時"
publish_date: "2015-12-21T06:37:51Z"
created: "2015-12-21T06:37:51Z"
updated: "2026-02-27T10:44:46.839Z"
categories: ["iOS"]
keywords: ""
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lang: "en"
---

# When Duplicate Symbol _OBJC_CLASS_ Appears in Large Numbers During iOS App Build

<div class="document">

<p>When encountering a large number of duplicate symbol _OBJC_CLASS_ errors during an iOS app build</p>
<p>After updating CocoaPods and building the project, I encountered a linker error. Upon examining the message, I noticed a large number of duplicate symbol _OBJC_CLASS_$_ errors.</p>
<p>→ Check the project's Build Settings → Other Linker Flags.</p>
<pre class="literal-block">
-ObjC
-l"Pods-AFNetworking"
-l"Pods-MBProgressHUD"
-l"Pods-SDWebImage"
-all_load
...
</pre>
<p>Remove all instances of -l"Pods-library name".</p>
<pre class="literal-block">
-ObjC
-all_load
...
</pre>
<p>It should look like this.</p>
<p>Build the project. → OK</p>
</div>