[JITLink] Dump weak-ref status for external symbols in LinkGraphs.

Coding my way home: 8.98112N, 79.52094W

Author: lhames

llvm/lib/ExecutionEngine/JITLink/JITLink.cpp

@@ -338,7 +338,8 @@ void LinkGraph::dump(raw_ostream &OS) {
   OS << "\nExternal symbols:\n";
   if (!external_symbols().empty()) {
     for (auto *Sym : external_symbols())
-      OS << "  " << Sym->getAddress() << ": " << *Sym << "\n";
+      OS << "  " << Sym->getAddress() << ": " << *Sym
+         << (Sym->isWeaklyReferenced() ? " (weakly referenced)" : "") << "\n";
   } else
     OS << "  none\n";
 }