Index: llvm/tools/llc/llc.cpp
===================================================================
--- llvm/tools/llc/llc.cpp
+++ llvm/tools/llc/llc.cpp
@@ -192,7 +192,10 @@
   cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
 
   cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
-
+  if (argc == 1) {
+    llvm::errs() << "Try: '" << argv[0] << " -help'\n";
+    return 1;
+  }
   // Compile the module TimeCompilations times to give better compile time
   // metrics.
   for (unsigned I = TimeCompilations; I; --I)
Index: llvm/tools/llvm-mc/llvm-mc.cpp
===================================================================
--- llvm/tools/llvm-mc/llvm-mc.cpp
+++ llvm/tools/llvm-mc/llvm-mc.cpp
@@ -356,6 +356,10 @@
   cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
 
   cl::ParseCommandLineOptions(argc, argv, "llvm machine code playground\n");
+  if (argc == 1) {
+    llvm::errs() << "Try: '" << argv[0] << " -help'\n";
+    return 1;
+  }
   MCTargetOptions MCOptions = InitMCTargetOptionsFromFlags();
   TripleName = Triple::normalize(TripleName);
   setDwarfDebugFlags(argc, argv);