Regression: compiling a macOS framework with the old build system produces Invalid bitcode signature

Number:rdar://37450480 Date Originated:12-Feb-2018 08:09 AM
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 9.3b2
Classification:Serious Bug Reproducible:Always
This is a regression from Xcode 8.2.1, where it linked warning-free.
It does work with the new build system, however we’re blocked on rdar://35488529 and thus still use the old build system for all builds across platforms.

Steps to Reproduce:
Unsure what to deliver to reproduce. This cannot be reproduced in a sample app.

Expected Results:
Compile same as Xcode 9.2.1 or new build system.

Actual Results:
Invalid bitcode signature linker error

Xcode 9.3b2

I also added -v as per Ankit Aggarwal’s comment on Twitter, but it did not yield any more useful data. (


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