How to link binary with libraries with SPM and Xcode11

Using Swift
1

Hi,

I started to use xcode 11 and I'm really impressed by the new feature Swift Package Manger I really like it and move some of my project with it.

One of my framework is a a Swift wrapper around c++ libraries. Theses libraries are static libraries and I cannot change it.
I'm trying to configure the Package.swift but I didn't have any success.

I create 2 targets one with all the c++ and objective-c++ files and one other with the Swift file.

My package looks like this:

// swift-tools-version:5.1
import PackageDescription

let package = Package(
  name: "MyFrameworkSDK",
  platforms: [.iOS(.v9)],
  products: [
    .library(
      name: "MyFrameworkSDK",
      targets: ["MyFrameworkSDK"]
    ),
  ],
  dependencies: [
    .package(url: "https://github.com/Alamofire/Alamofire", from: "4.9.0"),
    .package(url: "https://github.com/realm/realm-cocoa", from: "3.19.0"),
    .package(url: "https://github.com/SwiftyJSON/SwiftyJSON", from: "5.0.0")
  ],
  targets: [
    .target(
      name: "CPP",
      path: "Sources/CPP",
      cxxSettings: [
        .headerSearchPath("signalProcessingSDK/include/SignalProcessing"),
        .headerSearchPath("signalProcessingSDK/include/MyCPPSDK"),
        .headerSearchPath("signalProcessingSDK/include"),
        .headerSearchPath("CPPSignalProcessing/Codebridge"), // objective-c++ bridge
        .headerSearchPath("CPPSignalProcessing/SignalProcessing.Cpp")
      ],
      linkerSettings: [
        .unsafeFlags(["-LsignalProcessingSDK/lib", "-llibAlgebra"]) // Thise line seems not to work in the client project
      ]
    ),
    .target(
      name: "MyFrameworkSDK",
      dependencies: ["Alamofire", "RealmSwift", "SwiftyJSON", "CPP"],
      path: "Sources/Swift"
    )
  ],
  swiftLanguageVersions: [.v5],
  cxxLanguageStandard: .gnucxx11
)

I get the following error in the client:

d: warning: directory not found for option '-LsignalProcessingSDK/lib'
ld: library not found for -llibAlgebra

So my questions are:

  1. Is "unsafeFlags" is the right command to use to link binary with libraries? If not what should I use?
  2. Is the path given to "unsafeFlags" absolute or relative to the target?

Thanks for your help.

2

We don't support including precompiled binaries in Swift packages, yet, except for libraries and frameworks installed on the system. There is a pitch proposal for this feature: [PITCH] Support for binary dependencies - #95 by abertelrud

You can use unsafeFlags to still do it, but this will mean your package is not usable as a transitive dependency, so that's not really suitable for your case where you want to provide a framework.

If "signalProcessingSDK" is a set of libraries you are building with a different build system today, you could look into turning it into a package itself.