Duplicate library warning in Xcode 15 Beta

[rzulkoski]

Describe the bug

When building a project that brings in Bugsnag through SPM in Xcode 15 the following warning is shown:

Steps to reproduce

1. Open a project that brings in Bugsnag through SPM in Xcode 15
2. Build the project
3. See warnings

Environment

• Bugsnag version: 6.27.2
• iOS/tvOS/macOS version(s): iOS 17.0 beta 7
• Simulator or physical device: Both
• Xcode version: Xcode 15.0 Beta 7 (15A5229h)
• Swift version (if applicable): 5.9

Error messages:

ld: warning: ignoring duplicate libraries: '-lc++', '-lz'

[rzulkoski]

Sentry appears to have fixed these warnings by removing the linker settings from their Package.swift.

getsentry/sentry-cocoa#3122 (comment)

[mclack]

Hi @rzulkoski
Thanks for bringing this to our attention. We are currently investigating this and will look to get it fixed. We'll make sure to post any updates on this thread.

[jnozzi]

Hi there! Is there any update on this? I imagine I'm not the only one running afoul of "warnings as errors" in the CI process. 😆

[clr182]

Hi @jnozzi
We have no update on this just yet, however we will be sure to update this thread when we have more information to share.

[chickdan]

FYI I'm also seeing this warning via Cocoapods in Xcode 15.

[mclack]

Thank you all for your patience while we've been looking into this.

This issue looks to be caused by an incompatibility of the current GCC compiler and Xcode 15. It has been raised here, and a fix has been promised.

After investigating possible changes we could make to our project files, it currently seems highly unlikely we'll find an appropriate resolution before getting a fix from Homebrew.

Because of the above, the short term workarounds we recommend are either of the following:

1. Use version 14 of the Xcode Command Line Tools.
2. Update each target that reports the warning to add "-Wl -ld_classic" to the OTHER_LINKER_FLAGS build setting.

As this is just a warning, these immediate workarounds will only be required for those of you who treat warnings as errors.

[jnozzi]

I’ve just discovered that the more sharply-focused -Xlinker -no_warn_duplicate_libraries in OTHER_LINKER_FLAGS is sufficient under XC15.