Swift Package依赖GoogleMobileAds致项目编译链接错误求助

问题现象 #

• 自定义Swift Package（MikrasyaLibraryAds）依赖GoogleMobileAds，自身编译无报错
• 通过GitHub将该包添加到主项目后，Package Dependencies栏可正常看到GoogleMobileAds及其依赖GoogleUserMessagingPlatform
• 主项目编译失败，抛出Undefined symbols及Linker command failed with exit code 1错误，且target的「Frameworks, Libraries, and Embedded Content」中找不到GoogleMobileAds

自定义Package.swift代码 #

let package = Package(
    name: "MikrasyaLibraryAds",
    platforms: [.iOS(.v15)],
    products: [
        .library(
            name: "MikrasyaLibraryAds",
            targets: ["MikrasyaLibraryAds"]),
    ],
    dependencies: [
        .package(url: "https://github.com/googleads/swift-package-manager-google-mobile-ads.git", branch: "main"),
    ],
    targets: [
        .target(
            name: "MikrasyaLibraryAds",
            dependencies: [ .product(name: "GoogleMobileAds", package: "swift-package-manager-google-mobile-ads"),
                          ]
        ),
    ]
)

编译日志 #

ld: warning: Could not find or use auto-linked framework 'CoreAudioTypes': framework 'CoreAudioTypes' not found
ld: warning: Could not find or use auto-linked framework 'MarketplaceKit': framework 'MarketplaceKit' not found
ld: Undefined symbols:
  enum case for MarketplaceKit.AppDistributor.testFlight(MarketplaceKit.AppDistributor.Type) -> MarketplaceKit.AppDistributor, referenced from:
      l007 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
      l008 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
  enum case for MarketplaceKit.AppDistributor.marketplace(MarketplaceKit.AppDistributor.Type) -> (Swift.String) -> MarketplaceKit.AppDistributor, referenced from:
      l007 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
      l008 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
  enum case for MarketplaceKit.AppDistributor.other(MarketplaceKit.AppDistributor.Type) -> MarketplaceKit.AppDistributor, referenced from:
      l007 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
      l008 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
  static MarketplaceKit.AppDistributor.current.getter : MarketplaceKit.AppDistributor, referenced from:
      function signature specialization <Arg[0] = Dead> of static GoogleMobileAds.GADMarketplaceKitSignals.appDistributor() async -> Swift.String in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
  async function pointer to static MarketplaceKit.AppDistributor.current.getter : MarketplaceKit.AppDistributor, referenced from:
      function signature specialization <Arg[0] = Dead> of static GoogleMobileAds.GADMarketplaceKitSignals.appDistributor() async -> Swift.String in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
  enum case for MarketplaceKit.AppDistributor.appStore(MarketplaceKit.AppDistributor.Type) -> MarketplaceKit.AppDistributor, referenced from:
      l007 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
      l008 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
  type metadata accessor for MarketplaceKit.AppDistributor, referenced from:
      l007 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
      l008 in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
  nominal type descriptor for MarketplaceKit.AppDistributor, referenced from:
      _symbolic _____Sg 14MarketplaceKit14AppDistributorO in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
  __swift_FORCE_LOAD_$_swiftXPC, referenced from:
      __swift_FORCE_LOAD_$_swiftXPC_$_GoogleMobileAds in GoogleMobileAds[arm64][399](GADMarketplaceKitSignals.o)
clang: error: linker command failed with exit code 1 (use -v to see invocation)

额外观察 #

• 移除自定义包，直接给主项目添加GoogleMobileAds，编译正常
• 同时保留自定义包和直接添加的GoogleMobileAds，仍会触发编译错误

解决方案 #

1. 锁定GoogleMobileAds稳定版本
   避免使用main分支（可能包含未稳定代码），切换到官方推荐的稳定版本。修改Package.swift中的依赖声明：

   .package(url: "https://github.com/googleads/swift-package-manager-google-mobile-ads.git", from: "11.0.0"),
   

   版本号可根据官方最新稳定版调整。

2. 显式声明传递依赖的链接设置
   Swift Package默认不会自动传递底层依赖的链接规则，需在自定义包的target中添加linkerSettings：

   .target(
       name: "MikrasyaLibraryAds",
       dependencies: [
           .product(name: "GoogleMobileAds", package: "swift-package-manager-google-mobile-ads")
       ],
       linkerSettings: [
           .linkedFramework("MarketplaceKit"),
           .linkedFramework("CoreAudioTypes")
       ]
   ),
   

3. 清理缓存后重新构建

   • 执行File > Packages > Reset Package Caches
   • 执行Product > Clean Build Folder
   • 重新编译项目

4. 检查主项目编译配置

   • 确保主项目的iOS Deployment Target不低于自定义Package指定的iOS 15
   • 确认Build Options中的Enable Linking with Swift Libraries已勾选

内容的提问来源于stack exchange，提问作者Mikrasya