[PATCH] D14623: [ThinLTO] Comdat importing fixes and related cleanup

[Rafael Espíndola via llvm-commits]

> The above is what we will end up with either the existing module
> linker code (which converts the alias f() to a decl immediately when
> the prototypes are linked) and with this patch (which converts the
> alias to a decl after lazy linking is complete). I moved the import of
> f() to a later conversion to decl since with the patch we may decide
> to lazy link additional comdat groups and don't know whether the
> aliasee f2() is imported here until after lazy linking is complete.
> Even with your recent change to not allow importing aliases to
> available_externally functions, if the aliasee were linkonce we could
> import it and leave f() as an alias to the imported f2().

How is that so? The aliasee is in the same comdat as the alias. We
either decide to include both or none.

Cheers,
Rafael