Integrating a Framework (having Swift) in a strict ObjC consuming Project

Using Swift
1

If your consuming (or sample) project is fully ObjC, no single line (or no empty file) of Swift, and you want to consume a Framework that has Swift. I know the typical "trick" of using an empty.swift file, but is there something more "neat"?

2

Do you really need to do anything? I have just set up a project like that and can’t remember doing anything extra. In the worst case the linker will forget to include Swift runtime, but that can be fixed with a single flag.

3

Which flag would that be? From my test right now this is what adding a .swift file adds:

LastSwiftMigration = 0940;
CLANG_ENABLE_MODULES = YES;
SWIFT_OPTIMIZATION_LEVEL = "-Onone";   /* Only in DEBUG Configuration */
SWIFT_VERSION = 3.0;
4

It’s Always Embed Swift Standard Libraries, not sure about the symbol, not at a (proper) computer right now.

5

That's interesting (Always Embed) but my project works without this.

6

It works but the binary will be rejected by the App Store.

7

BTW if you don't do anything not even the linker complains but the runtime does:

dyld: Library not loaded: @rpath/libswiftCore.dylib
  Referenced from: /path.to/ObjC.app/Frameworks/Driver.framework/Driver
  Reason: image not found
(lldb)
8

So from my test I don't need any of the the flags up there that are added when I add a file, but I only need ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES. Thanks @zoul and @gwendal.roue for helping. It was important for me to know what I need to tell to the users of the framework.

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