Following up to the list after discussion on IRC: The underlying problem is the upstream (qemu) build system. Qemu is normally built using the C++ compiler which (at least on GCC/Linux) always links with -lm.
liuw's rump kernel build was using the C compiler instead which does not do that. Solution: Submit a patch to Qemu to fix the issue when not building with a C++ compiler. We will not be adding -lm to the default link set for the C toolchain.
