Follow-up Comment #5, sr #111069 (group libtool):
Actually, checking the behaviour of ld64 when it's given unknown flags isn't
hard:
```
❯ clang -xc - -Wl,-nonexistent_flag -o /dev/null <<<'int main(){}'
ld: unknown options: -nonexistent_flag
clang: error: linker command failed with exit code 1
Follow-up Comment #4, sr #111069 (group libtool):
[comment #3 comment #3:]
> I personally tested this a while back
Thanks for letting me know about that testing. Now I wonder if a feature test
might be better here in libtool, rather than a linker version number test.
Follow-up Comment #3, sr #111069 (group libtool):
> My original patch assumes that `-no_fixup_chains` would be silently ignored
by intermediate linker versions older than Xcode 13. I have not yet tested
this assumption on any such Macs.
This is not a good assumption, I'm afraid. I personally
