Compiling apr fails while having libtool-2 installed, but it works just fine with libtool-1.5. Reproducible: Always Steps to Reproduce:
For me, it builds just fine with libtool-2, so unless you can prove otherwise, it's probably invalid.
I tried it in a x86 chroot inside an amd64 box, and it failed (screaming something about --tag) until I downgraded libtool to 1.5, which worked, but it seems I can't reproduce it aymore with libtool2. I'm sorry for the false alarm.