Put more stuff in the comdat used for variables with static init

[Rafael Espíndola]

On 18 September 2014 19:35, Reid Kleckner <rnk at google.com> wrote:
> We should also omit the third entry in @llvm.global_ctors.

Should llvm also err when the third field is not null and we are
producing MachO? Seems reasonable since the spec says

If the third field is present, non-null, and points to a global
variable or function, the initializer function will only run if the
associated data from the current module is not discarded.

And I don't think there is a way to implement that on MachO.

Cheers,
Rafael