[ELF] Replace lld::warn with Warn(ctx)

Author: MaskRay

lld/ELF/Driver.cpp

@@ -641,7 +641,7 @@ void LinkerDriver::linkerMain(ArrayRef<const char *> argsArr) {
   ELFOptTable parser;
   opt::InputArgList args = parser.parse(ctx, argsArr.slice(1));
 
-  // Interpret these flags early because error()/warn() depend on them.
+  // Interpret these flags early because Err/Warn depend on them.
   errorHandler().errorLimit = args::getInteger(args, OPT_error_limit, 20);
   errorHandler().fatalWarnings =
       args.hasFlag(OPT_fatal_warnings, OPT_no_fatal_warnings, false) &&

lld/ELF/Symbols.cpp

@@ -321,7 +321,7 @@ void elf::maybeWarnUnorderableSymbol(Ctx &ctx, const Symbol *sym) {
   auto *d = dyn_cast<Defined>(sym);
 
   auto report = [&](StringRef s) {
-    warn(toStr(ctx, file) + s + sym->getName());
+    Warn(ctx) << toStr(ctx, file) << s << sym->getName();
   };
 
   if (sym->isUndefined()) {