Cosmopolitan Build

Cosmopolitan libc "makes C a build-anywhere run-anywhere language".

This is very appealing for us. Cosmopolitan also supports a reasonable set of POSIX system calls - even on non-POSIX platforms. So we can write POSIXy C++ and release a single binary for many platforms and hardware architectures.

To build Vampire with the Cosmopolitan toolchain, first install Cosmopolitan, then checkout the cosmopolitan branch. Michael will try and keep this up to date - all it does is tinker with CMakeLists a bit to patch around things not-yet supported in Cosmopolitan. Then set CMAKE_CXX_COMPILER=/path/to/cosmoc++ and build as usual. You'll probably get some warnings about signal handlers, but they don't seem to hurt.