title: Flutter Ignoring ffi-1.12.2 because its extensions are not built. Try: gem pristine ffi --version 1.12.2
body: <p>When i  try to build <strong>Flutter project</strong> to <strong>IOS</strong> it show me this error, I have tried to clean and also tried to change the directory of the project.</p>
  <pre><code>Launching lib/main.dart on iPhone 12 Pro Max in debug mode... Running pod install... CocoaPods' output: ↳
  
      [!] Invalid `Podfile` file: [!] Specifying multiple `post_install` hooks is unsupported..
  
       #  from /Users/eapple/Downloads/codecanyon-IRJuYEQd-delivery-boy-for-multirestaurants-flutter-app/flutter_application/ios/Podfile:43
       #  -------------------------------------------
       #  
       &gt;  post_install do |installer|
       #    installer.pods_project.targets.each do |target|
       #  -------------------------------------------
  
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.9.1/lib/cocoapods-core/podfile.rb:301:in `rescue in block in from_ruby'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.9.1/lib/cocoapods-core/podfile.rb:295:in `block in from_ruby'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.9.1/lib/cocoapods-core/podfile.rb:50:in `instance_eval'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.9.1/lib/cocoapods-core/podfile.rb:50:in `initialize'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.9.1/lib/cocoapods-core/podfile.rb:293:in `new'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.9.1/lib/cocoapods-core/podfile.rb:293:in `from_ruby'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.9.1/lib/cocoapods-core/podfile.rb:259:in `from_file'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.1/lib/cocoapods/config.rb:200:in `podfile'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.1/lib/cocoapods/command.rb:150:in `verify_podfile_exists!'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.1/lib/cocoapods/command/install.rb:46:in `run'
      /Library/Ruby/Gems/2.6.0/gems/claide-1.0.3/lib/claide/command.rb:334:in `run'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.1/lib/cocoapods/command.rb:52:in `run'
      /Library/Ruby/Gems/2.6.0/gems/cocoapods-1.9.1/bin/pod:55:in `&lt;top (required)&gt;'
      /usr/local/bin/pod:23:in `load'
      /usr/local/bin/pod:23:in `&lt;main&gt;'
  
  Error output from CocoaPods: ↳
      Ignoring ffi-1.12.2 because its extensions are not built. Try: gem pristine ffi --version 1.12.2
  Error running pod install
  Error launching application on iPhone 12 Pro Max.
  </code></pre>
  <p>Here is the <strong>pubspec.yaml</strong> file</p>
  <pre><code>  cupertino_icons: 0.1.2
    google_maps_flutter: 0.5.27
    mvc_pattern: 5.1.1
    global_configuration: 1.5.0
    http: 0.12.1
    html: 0.14.0+3
    shared_preferences: 0.5.7
    flutter_html: 0.11.1
    location: 3.0.2
    url_launcher: 5.4.5
    firebase_messaging: 6.0.13
    cached_network_image: 2.2.0
    fluttertoast: 4.0.1
  </code></pre>
  <p><strong>Things I have tried, from common sense and various other Stack questions:</strong></p>
  <ul>
  <li><p><code>flutter clean</code></p>
  </li>
  <li><p>Adding this to <code>ios/Podfile</code></p>
  <pre><code>post_install do |installer|
      installer.pods_project.targets.each do |target|
        target.build_configurations.each do |config|
          config.build_settings['SWIFT_VERSION'] = '4.0'
         end
       end
    end
  </code></pre>
  </li>
  <li><p><code>flutter pub get</code></p>
  </li>
  <li><p>installing <code>gem install ffi --version 1.13.1 --user-install</code></p>
  </li>
  </ul>