Subzero: Fix the g++ build (e.g. Windows).

src/IceELFSection.cpp

 //===- subzero/src/IceELFSection.cpp - Representation of ELF sections -----===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file defines how ELF sections are represented.
@@ skipping 37 matching lines @@
   NewSymbol.Sym.st_value = Offset;
   NewSymbol.Sym.st_size = Size;
   NewSymbol.Number = ELFSym::UnknownNumber;
   SymtabKey Key = {Name, Section};
   bool Unique;
   if (Type == STB_LOCAL)
     Unique = LocalSymbols.insert(std::make_pair(Key, NewSymbol)).second;
   else
     Unique = GlobalSymbols.insert(std::make_pair(Key, NewSymbol)).second;
   assert(Unique);
+  (void)Unique;
 }
 
 void ELFSymbolTableSection::noteUndefinedSym(const IceString &Name,
                                              ELFSection *NullSection) {
   ELFSym NewSymbol = ELFSym();
   NewSymbol.Sym.setBindingAndType(STB_GLOBAL, STT_NOTYPE);
   NewSymbol.Number = ELFSym::UnknownNumber;
   SymtabKey Key = {Name, NullSection};
   GlobalSymbols.insert(std::make_pair(Key, NewSymbol));
 }
@@ skipping 82 matching lines @@
       continue;
     }
     StringIndex.second = StringData.size();
     std::copy(Cur.begin(), Cur.end(), back_inserter(StringData));
     StringData.push_back(0);
     Prev = Cur;
   }
 }
 
 } // end of namespace Ice