ELF: Enable address-significance tables during LTO.

This allows safe ICF to work when linking with LTO.

Differential Revision: https://reviews.llvm.org/D50221

llvm-svn: 339050
diff --git a/lld/ELF/LTO.cpp b/lld/ELF/LTO.cpp
index ef58932..cb5bb64 100644
--- a/lld/ELF/LTO.cpp
+++ b/lld/ELF/LTO.cpp
@@ -67,9 +67,10 @@
 static lto::Config createConfig() {
   lto::Config C;
 
-  // LLD supports the new relocations.
+  // LLD supports the new relocations and address-significance tables.
   C.Options = InitTargetOptionsFromCodeGenFlags();
   C.Options.RelaxELFRelocations = true;
+  C.Options.EmitAddrsig = true;
 
   // Always emit a section per function/datum with LTO.
   C.Options.FunctionSections = true;