Print more information about duplicated symbols.

llvm-svn: 248380
diff --git a/lld/ELF/SymbolTable.h b/lld/ELF/SymbolTable.h
index bd69290..5f539b3 100644
--- a/lld/ELF/SymbolTable.h
+++ b/lld/ELF/SymbolTable.h
@@ -70,6 +70,8 @@
 
   template <class ELFT> void init(uint16_t EMachine);
   template <class ELFT> void resolve(SymbolBody *Body);
+  template <class ELFT>
+  void dupErorr(const SymbolBody &Old, const SymbolBody &New);
 
   std::vector<std::unique_ptr<ArchiveFile>> ArchiveFiles;