@twobob: I'm not sure what you meant :?
Your host (your system's native TC) is using, well, native stuff, probably x86 or x86_64, depending on your setup. You X-TC should be using stuff targeted at the target's arch, arm, in our cases.
To get back on the multiple glibc thing, if you keep it away from search paths, it's completely harmless.
For example, I have a crapload of different TCs in a folder in my $HOME. Each TC is in a separate subfolder there, and my searchpaths always contains only *one* of these x-tc when I'm x-building stuff. When I'm not, I don't tweak my searchpaths