[lto] added getCOFFWeakExternalFallback

Summary: This allows clients of the LTO API to determine the name of the fallback symbol for COFF weak externals.

Reviewers: pcc

Reviewed By: pcc

Subscribers: mehdi_amini

Differential Revision: https://reviews.llvm.org/D29365



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293960 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed