# How to Solve "Building for iOS Simulator, but linking in dylib built for iOS"

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Dynamsoft framework can be used to build an app for arm64 iOS. If you build the app for arm64 simulator and you are migrating your app from older versions to Xcode 12 or higher, the following error message may pop up:  

> ld: "Building for iOS Simulator, but linking in dylib built for iOS, file '/ios/Pods/DynamsoftBarcodeReader/DynamsoftBarcodeReader.xcframework/DynamsoftBarcodeReader' for architecture arm64"  

<br />

**To fix the error:**  

1. Set *Build Settings* > *Build Options* > *VALIDATE_WORKSPACE* to "YES" and then rebuild your project  
2. Set *Build Settings* > *Architectures* > *Build Active Architecture Only* to "YES" and run on an iPhone device
3. Set *Build Settings* >  *Architectures* -> $(ARCHS_STANDARD)  

<br />

**If the error message still exists, please make one of the following changes:**  

Switch from framework to xcframeworks  

Or  

Excluded Architectures -> Debug -> Any iPhone simulator -> arm64  

Or  

```ruby
Podfile:
post_install do |installer|
  installer.pods_project.build_configurations.each do |config|
    config.build_settings["EXCLUDED_ARCHS[sdk=iphonesimulator*]"] = "arm64"
  end
end
```

Or  

```ruby
post_install do |installer|
  installer.pods_project.build_configurations.each do |config|
    config.build_settings["EXCLUDED_ARCHS[sdk=iphonesimulator*]"] = "uname -m"
  end
end
```

Or  

```ruby
podspec:
s.pod_target_xcconfig = { 'EXCLUDED_ARCHS[sdk=iphonesimulator*]' => 'arm64' }
s.user_target_xcconfig = { 'EXCLUDED_ARCHS[sdk=iphonesimulator*]' => 'arm64' }
```