1 files changed, 19 insertions, 13 deletions
diff --git a/llvm/lib/ToolDrivers/llvm-lib/LibDriver.cpp b/llvm/lib/ToolDrivers/llvm-lib/LibDriver.cpp
index 286191abff202..c409012554245 100644
--- a/llvm/lib/ToolDrivers/llvm-lib/LibDriver.cpp
+++ b/llvm/lib/ToolDrivers/llvm-lib/LibDriver.cpp
@@ -59,13 +59,10 @@ public:
 
 }
 
-static std::string getOutputPath(opt::InputArgList *Args,
-                                 const NewArchiveMember &FirstMember) {
-  if (auto *Arg = Args->getLastArg(OPT_out))
-    return Arg->getValue();
+static std::string getDefaultOutputPath(const NewArchiveMember &FirstMember) {
   SmallString<128> Val = StringRef(FirstMember.Buf->getBufferIdentifier());
   sys::path::replace_extension(Val, ".lib");
-  return Val.str();
+  return std::string(Val.str());
 }
 
 static std::vector<StringRef> getSearchPaths(opt::InputArgList *Args,
@@ -96,7 +93,7 @@ static std::string findInputFile(StringRef File, ArrayRef<StringRef> Paths) {
     SmallString<128> Path = Dir;
     sys::path::append(Path, File);
     if (sys::fs::exists(Path))
-      return Path.str().str();
+      return std::string(Path);
   }
   return "";
 }
@@ -144,14 +141,14 @@ static void doList(opt::InputArgList& Args) {
 
 static COFF::MachineTypes getCOFFFileMachine(MemoryBufferRef MB) {
   std::error_code EC;
-  object::COFFObjectFile Obj(MB, EC);
-  if (EC) {
+  auto Obj = object::COFFObjectFile::create(MB);
+  if (!Obj) {
     llvm::errs() << MB.getBufferIdentifier()
-                 << ": failed to open: " << EC.message() << '\n';
+                 << ": failed to open: " << Obj.takeError() << '\n';
     exit(1);
   }
 
-  uint16_t Machine = Obj.getMachine();
+  uint16_t Machine = (*Obj)->getMachine();
   if (Machine != COFF::IMAGE_FILE_MACHINE_I386 &&
       Machine != COFF::IMAGE_FILE_MACHINE_AMD64 &&
       Machine != COFF::IMAGE_FILE_MACHINE_ARMNT &&
@@ -292,8 +289,9 @@ int llvm::libDriverMain(ArrayRef<const char *> ArgsArr) {
     return 0;
   }
 
-  // If no input files, silently do nothing to match lib.exe.
-  if (!Args.hasArgNoClaim(OPT_INPUT))
+  // If no input files and not told otherwise, silently do nothing to match
+  // lib.exe
+  if (!Args.hasArgNoClaim(OPT_INPUT) && !Args.hasArg(OPT_llvmlibempty))
     return 0;
 
   if (Args.hasArg(OPT_lst)) {
@@ -352,7 +350,15 @@ int llvm::libDriverMain(ArrayRef<const char *> ArgsArr) {
   }
 
   // Create an archive file.
-  std::string OutputPath = getOutputPath(&Args, Members[0]);
+  std::string OutputPath;
+  if (auto *Arg = Args.getLastArg(OPT_out)) {
+    OutputPath = Arg->getValue();
+  } else if (!Members.empty()) {
+    OutputPath = getDefaultOutputPath(Members[0]);
+  } else {
+    llvm::errs() << "no output path given, and cannot infer with no inputs\n";
+    return 1;
+  }
   // llvm-lib uses relative paths for both regular and thin archives, unlike
   // standard GNU ar, which only uses relative paths for thin archives and
   // basenames for regular archives.