Open Radar

 
Summary:
If you use #if to disable building a file in a particular configuration, and that file contains @objc, the build will spuriously fail.

Steps to Reproduce:
- Download the attached sample
- Try to compile it:

xcrun swift if-objc.swift -o if-objc

Expected Results:
It should compile w/ no symbols emitted since the entire file is #if'd out

Actual Results:
if-objc.swift:14:2: error: @objc attribute used without importing module 'Foundation'

(even though Foundation was imported, so presumably the Swift compiler's lack of textual processing of #if means it is manually disabling compiler features as they are invoked and @objc was missed).


Version:
Xcode 7.2b3

Notes:


Configuration:
All

Example:

/*
Radar 23487944

% xcrun swift if-objc.swift -o if-objc
if-objc.swift:14:2: error: @objc attribute used without importing module 'Foundation'
@objc public protocol FooProtocol {
~^~~~

*/

#if FOO_ENABLED

import Foundation
@objc public protocol FooProtocol {
	
}

@objc public class Foo : NSObject, FooProtocol {
	
}

#endif