Common symbols are not undefined, at least for ObjectFile.

They are implemented like that in some object formats, but for the interface
provided by lib/Object, SF_Undefined and SF_Common are different things.

This matches the ELF and COFF implementation and fixes llvm-nm for MachO.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241587 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed