Right. A 64-bit rpm that's entirely 32-bit. I had run
file *.so* |grep 32
and foujnd everything. Then
file *.so* |grep 64
found my symlink to libGL.so in /usr/lib64. I'm on an advanced mesa on that box, and have llvm set up because the vertex shader is crap on the video card. There is a vague memory of a --with-llvm option in there somewhere, which slackware doesn't use.
I am _not_ going to recompile mesa32 bit, or even rob the (different version) mesa libs from this 32 bit box. Not even once. I am going to uninstall googleearth, which seems the obvious solution. Thank heavens I was tidy enough to put it in a package.