I looked into the changelog for 2.34, which this website claims removed 24 symbols.

* 9 malloc debugging variables were removed, though their symbols actually remain for backwards compatibility they just don't do anything. * vtimes was removed, but the symbol remains for backwards compatibility

Those were the only changelog entries listing removals. None of them cause linking issues. The 9 that did break backwards compatibility are a set of debug tools that don't work for alternate memory allocators and the functionality can be brought back with libc_malloc_debug.so.

Maybe the changelog's incomplete, but this actually seem pretty tame to me.

The nastiest removal I'm aware of is `crypt`, and even in that case it's just a matter of adding the appropriate `LD_PRELOAD` if you can't relink.