Could you elaborate?
As I remember, these features rely heavily on linker support, namely on how it merges sections. Each pointer to static ctor (and unittest) is placed in a section, then these sections are merged by linker and you get an array of pointers to all static ctors and unittests. The startup code reads the pointers in sequence and executes them. If some section is removed, the corresponding static ctor won't be run.
Real code, that i was testing with previously, contained static module ctors which worked, and i just tried a simple two module test w/ multiple shared_[cd]tors + static_[cd]tors + unittests -- all of them are called as expected.
If so then ok.