Any way to get rid of "Module compiled with Swift X.X cannot be imported by Swift X.X compiler" error?

[hardeverick]

Hi,

Every time I update Xcode I get this error and I have to manually specify the Swift version for some pods to match the Swift compiler in the version of Xcode I'm using. I looked online and this answer suggests setting the option BUILD_LIBRARY_FOR_DISTRIBUTION but it doesn't seem to work.

This is my Podbuilder.json file

{
  "project_name": "HAR",
  "spec_overrides": {
    "Google-Mobile-Ads-SDK": {
      "module_name": "GoogleMobileAds"
    },
    "glog": {
      "pod_target_xcconfig": {
        "DEFINES_MODULE": "NO"
      }
    },
    "DoubleConversion": {
      "pod_target_xcconfig": {
        "DEFINES_MODULE": "NO"
      }
    },
    "Folly": {
      "pod_target_xcconfig": {
        "DEFINES_MODULE": "NO"
      }
    },
    "Flipper-DoubleConversion": {
      "pod_target_xcconfig": {
        "DEFINES_MODULE": "NO"
      }
    },
    "Flipper-Folly": {
      "pod_target_xcconfig": {
        "DEFINES_MODULE": "NO"
      }
    },
    "AlignedCollectionViewFlowLayout": {
      "swift_version": "5.6"
    },
    "RealmSwift": {
      "swift_version": "5.6"
    },
    "SwiftHash": {
      "swift_version": "5.6"
    },
    "SwiftSimplify": {
      "swift_version": "5.6"
    },
    "FloatingPanel": {
      "swift_version": "5.6"
    },
    "ActiveLabel": {
      "swift_version": "5.6"
    }
  },
  "skip_licenses": [

  ],
  "skip_pods": [
    "GoogleMaps",
    "React-RCTFabric",
    "React-Core",
    "React-CoreModules"
  ],
  "force_prebuild_pods": [

  ],
  "build_settings": {
    "ENABLE_BITCODE": "NO",
    "GCC_OPTIMIZATION_LEVEL": "s",
    "SWIFT_OPTIMIZATION_LEVEL": "-Osize",
    "SWIFT_COMPILATION_MODE": "wholemodule",
    "CODE_SIGN_IDENTITY": "",
    "CODE_SIGNING_REQUIRED": "NO",
    "CODE_SIGN_ENTITLEMENTS": "",
    "CODE_SIGNING_ALLOWED": "NO",
    "BUILD_LIBRARY_FOR_DISTRIBUTION": "YES"
  },
  "build_settings_overrides": {
    "SBTUITestTunnelClient": {
      "ENABLE_BITCODE": "NO"
    }
  },
  "build_system": "Latest",
  "library_evolution_support": false,
  "license_filename": "Pods-acknowledgements",
  "restore_enabled": true,
  "allow_building_development_pods": false,
  "use_bundler": false,
  "deterministic_build": false,
  "build_using_repo_paths": false,
  "react_native_project": false
}

[tcamin]

Hi, instead of setting "BUILD_LIBRARY_FOR_DISTRIBUTION": "YES" you should set "library_evolution_support": true (see https://github.com/Subito-it/PodBuilder#library_evolution_support).

In general however I would advise to set "build_xcframeworks_all": true (which implies library evo support) which will produce xcframeworks adding Apple Silicon support

[hardeverick]

Thanks for the reply @tcamin

I tried this and I'm no longer getting the cannot be imported error, but I'm getting a lot these errors (see screenshot below): is there anything else I'm doing wrong?

Thanks

[hardeverick]

@tcamin It seems like this is caused because the Module and class name are the same according to this https://developer.apple.com/forums/thread/123253. There's a proposed fix in that link that runs this command find . -name "*.swiftinterface" -exec sed -i -e 's/frameworkName\.//g' {} \;. Is there something similar that I could run in PodBuilder?

[hardeverick]

In the mean time I worked around the problem by switching the pods with problems to use SPM (Swift Package Manager).

[tcamin]

You should be able to patch the switfinterface files by adding this to your Podfile

post_install do |installer|
  swift_interface_paths = Dir.glob("./PodBuilder/Prebuilt/RealmSwift/**/*.swiftinterface")
  swift_interface_paths.each do |path|
      content = File.read(path)
      content.gsub!("Realm.RLM", "RLM")
      content.gsub!("Realm.Realm", "Realm")
      File.write(path, content)
  end
end

With respect to your workaround of using SPM you could alternatively just add the non working pods to the skip list as documented here