Circular dependencies are not just a problem for cross-compiling. They can make life difficult for anyone building their own packages. I came across this when building a newer set of perl packages for Fedora. Although the packages from upstream (CPAN) do not have circular deps, the Fedora source RPMs do, because of the practice of adding in all possible dependencies as hard deps, even if they are not needed to build the module but only for optional bits of the test suite. (Or perhaps not even that - sometimes a module was not needed for 'make test' but only for 'make author_test', which downstream users and packagers should not need to run at all.).
It would be better to have a distribution policy to avoid circular hard build dependencies whenever possible. Admittedly they are sometimes unavoidable.