[PATCH] [ELF] LLD does not create a record in the .dynsym if a strong symbol defined in the executable file replaces a weak symbol from a shared library.

[Shankar Easwaran]

The best way to do this is using a ELF reference that sets a dynamic export tag. We should not be adding a export dynamic to an atom as that's not a property.

http://reviews.llvm.org/D4789