升级Mac后，Flutter项目里的ios项目运行 pod install报错， 

遇到这种问题，不要着急去百度，大概看一下报错信息，每个人遇到的问题都不一样。

别人的解决方法并不一定适合你；

下面是报错信息：

### Error

```
LoadError - cannot load such file -- ffi_c
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/Library/Ruby/Gems/2.6.0/gems/ffi-1.17.1-arm64-darwin/lib/ffi.rb:5:in `rescue in <top (required)>'
/Library/Ruby/Gems/2.6.0/gems/ffi-1.17.1-arm64-darwin/lib/ffi.rb:2:in `<top (required)>'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/Library/Ruby/Gems/2.6.0/gems/ethon-0.15.0/lib/ethon.rb:3:in `<top (required)>'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/Library/Ruby/Gems/2.6.0/gems/typhoeus-1.4.0/lib/typhoeus.rb:2:in `<top (required)>'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.15.2/lib/cocoapods-core/cdn_source.rb:440:in `download_typhoeus_impl_async'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.15.2/lib/cocoapods-core/cdn_source.rb:372:in `download_and_save_with_retries_async'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.15.2/lib/cocoapods-core/cdn_source.rb:365:in `download_file_async'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.15.2/lib/cocoapods-core/cdn_source.rb:338:in `download_file'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.15.2/lib/cocoapods-core/cdn_source.rb:284:in `ensure_versions_file_loaded'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.15.2/lib/cocoapods-core/cdn_source.rb:208:in `search'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.15.2/lib/cocoapods-core/source/aggregate.rb:83:in `block in search'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.15.2/lib/cocoapods-core/source/aggregate.rb:83:in `select'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-core-1.15.2/lib/cocoapods-core/source/aggregate.rb:83:in `search'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:416:in `create_set_from_sources'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:385:in `find_cached_set'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:360:in `specifications_for_dependency'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:165:in `search_for'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:274:in `block in sort_dependencies'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:267:in `each'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:267:in `sort_by'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:267:in `sort_by!'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:267:in `sort_dependencies'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/delegates/specification_provider.rb:60:in `block in sort_dependencies'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/delegates/specification_provider.rb:77:in `with_no_such_dependency_error_handling'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/delegates/specification_provider.rb:59:in `sort_dependencies'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/resolution.rb:754:in `push_state_for_requirements'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/resolution.rb:744:in `require_nested_dependencies_for'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/resolution.rb:727:in `activate_new_spec'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/resolution.rb:684:in `attempt_to_activate'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/resolution.rb:254:in `process_topmost_state'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/resolution.rb:182:in `resolve'
/Library/Ruby/Gems/2.6.0/gems/molinillo-0.8.0/lib/molinillo/resolver.rb:43:in `resolve'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/resolver.rb:94:in `resolve'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/installer/analyzer.rb:1082:in `block in resolve_dependencies'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/user_interface.rb:64:in `section'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/installer/analyzer.rb:1080:in `resolve_dependencies'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/installer/analyzer.rb:125:in `analyze'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/installer.rb:422:in `analyze'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/installer.rb:244:in `block in resolve_dependencies'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/user_interface.rb:64:in `section'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/installer.rb:243:in `resolve_dependencies'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/installer.rb:162:in `install!'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/lib/cocoapods/command/install.rb:52: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-1.15.2/lib/cocoapods/command.rb:52:in `run'
/Library/Ruby/Gems/2.6.0/gems/cocoapods-1.15.2/bin/pod:55:in `<top (required)>'
/usr/local/bin/pod:23:in `load'
/usr/local/bin/pod:23:in `<main>'
```

――― TEMPLATE END ――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――

[!] Oh no, an error occurred.

Search for existing GitHub issues similar to yours:
https://github.com/CocoaPods/CocoaPods/search?q=cannot+load+such+file+--+ffi_c&type=Issues

If none exists, create a ticket, with the template displayed above, on:
https://github.com/CocoaPods/CocoaPods/issues/new

Be sure to first read the contributing guide for details on how to properly submit a ticket:
https://github.com/CocoaPods/CocoaPods/blob/master/CONTRIBUTING.md

Don't forget to anonymize any private data!

Looking for related issues on cocoapods/cocoapods...
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   https://github.com/CocoaPods/CocoaPods/issues/12635 [open] [5 comments]
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 - LoadError - cannot load such file -- ffi_c
   https://github.com/CocoaPods/CocoaPods/issues/12538 [closed] [3 comments]
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 - LoadError - cannot load such file -- ffi_c
   https://github.com/CocoaPods/CocoaPods/issues/12440 [closed] [19 comments]
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and 12 more at:
https://github.com/cocoapods/cocoapods/search?q=cannot%20load%20such%20file%20--%20ffi_c&type=Issues&utf8=✓

首先，找到了主要报错信息： 

LoadError - cannot load such file -- ffi_c 

就是这一行， 我一看难道是 ffi 的问题？？

于是， 就用下面这一行安装试一下； 结果？？ 

brew install ffi

结果，它就报了以下搞笑的信息：

Warning: You are using macOS 15.
We do not provide support for this pre-release version.
It is expected behaviour that some formulae will fail to build in this pre-release version.
It is expected behaviour that Homebrew will be buggy and slow.
Do not create any issues about this on Homebrew's GitHub repositories.
Do not create any issues even if you think this message is unrelated.
Any opened issues will be immediately closed without response.
Do not ask for help from Homebrew or its maintainers on social media.
You may ask for help in Homebrew's discussions but are unlikely to receive a response.
Try to figure out the problem yourself and submit a fix as a pull request.
We will review it but may or may not accept it.

Error: unknown or unsupported macOS version: :dunno  

我去， Homebrew这么Dior的吗？ 好吧，接下来需要先解决这个 Homebrew 在 macOS 15上不能用的问题， 我是用 Homebrew 比较多的，好多工具都是用的 brew 安装的。

经过一顿搜索，在苹果开发社区找到了答案：运行下面一行就能解决问题了。 

  brew update-reset

OK ， Homebrew 修好了，就赶紧 brew install ffi 试一试， 发现报错依旧。

于是，就又再次去看一下报错信息， 然后就发现报错信息里，频繁得在使用 ruby ，然后就查看了我的ruby版本， 又结合 AI 的回答，才发现，是苹果自带的ruby版本太低了， 这也是报错的原因。

然后，我就去安装了

brew install ruby  

安装完后， 运行

head -n 1 $(which pod)

来查一下， 它还会不会依赖旧版本的 ruby。 发现它还是依赖的旧版本。 

解决办法是，去环境变量配置， 我的是 ~/.bash_profile ，路径修改为你新安装的ruby文件夹路径 。 

export HOMEBREW_RUBY_PATH=$(which ruby)

我的路径是这样的：

export HOMEBREW_RUBY_PATH="/usr/local/opt/ruby/bin/ruby"

配置环境变量前，最好提前把 cocoapods 卸载。

然后就重新安装 cocoapods

brew install cocoapods

这时候重新安装的话，他就能依赖我们新安装的ruby了。 

运行下面这个， 可以验证一下，到底对不对。 

which pod
head -n 1 $(which pod)

cocoapods 安装完后， 再去pod install， 就都正常了， 熟悉的画面回来了。