Swift Mac Command Line Tool target cannot link with -ObjC flag in Xcode 7.3

Originator:amcknight2718
Number:rdar://25442928 Date Originated:3/30/16
Status:Closed as duplicate Resolved:
Product:Xcode Product Version:7.3 (7D175)
Classification:Serious bug Reproducible:Always
 
Description:
When linking, many duplicate symbol errors are thrown from the linker for ErrorObject and SwiftObject in libswiftRuntime.a and libswiftCore.a. This does not occur in Xcode 7.2.1

Repro steps:
1. Create new Xcode 7.3 project for a mac command line tool
2. Build and run to confirm everything works
3. Add -ObjC to OTHER_LDFLAGS
4. Try to build again
5. Try to build now in Xcode 7.2.1

Expected results: 
Project should build fine in both Xcode 7.2.1 and 7.3

Actual results:
LD fails due to the mentioned duplicate symbol errors in Xcode 7.3, but not in Xcode 7.2.1

Setup:
Version 7.3 (7D175), OS X 10.11.4 (15E65)

Sample project available at https://www.dropbox.com/s/0xqt4j1kzdzen6b/swift_cli_xcode7_3.zip?dl=0

Comments

Seconded, Fatal bug

Tried many, many ways to work around this with no success. This is is a critical bug for our app and completely prohibits using 7.3 in our development.

Apple pls

By Damouse007 at April 4, 2016, 3:13 p.m. (reply...)

We found a workaround

The only reason we were using -ObjC was to pull in some categories through a static library. How about you?

By amcknight2718 at April 5, 2016, 2:53 p.m. (reply...)

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