Add -help option to Darwin Driver. Use grouping in Options table to better format help output

llvm-svn: 186640

1 files changed, 6 insertions, 0 deletions

diff --git a/lld/lib/ReaderWriter/MachO/MachOTargetInfo.cpp b/lld/lib/ReaderWriter/MachO/MachOTargetInfo.cpp
index 0141e1aed89..4e3ae6cafe6 100644
--- a/lld/lib/ReaderWriter/MachO/MachOTargetInfo.cpp
+++ b/lld/lib/ReaderWriter/MachO/MachOTargetInfo.cpp
@@ -89,6 +89,7 @@ bool MachOTargetInfo::PackedVersion::operator==(
 MachOTargetInfo::MachOTargetInfo() 
   : _outputFileType(mach_o::MH_EXECUTE)
   , _outputFileTypeStatic(false)
+  , _doNothing(false)
   , _arch(arch_unknown)
   , _os(OS::macOSX)
   , _osMinVersion("0.0")
@@ -182,6 +183,11 @@ bool MachOTargetInfo::addUnixThreadLoadCommand() const {
 }
 
 bool MachOTargetInfo::validateImpl(raw_ostream &diagnostics) {
+  if (_inputFiles.empty()) {
+    diagnostics << "no object files specified\n";
+    return true;
+  }
+
   if ((_outputFileType == mach_o::MH_EXECUTE) && _entrySymbolName.empty()) {
     if (_outputFileTypeStatic) {
       _entrySymbolName = "start";