libtool: warning: 'Foo.o' has no symbols on Xcode 26.4

I've recently installed Xcode 26.4, and it seems like all of our libraries now give multiple linker error when building of the format libtool: warning: 'Foo.o' has no symbols

Most of these errors come from extensions over objc types written in objc. (for instance we have some extensions over NSArray in the file NSArray+NSSet.mm)

Is that a new feature of some stricter libtool invocation? or a bug? should I do anything about it?

libtool: warning: 'Foo.o' has no symbols on Xcode 26.4
 
 
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