Index: lib/ObjectYAML/ObjectYAML.cpp
===================================================================
--- lib/ObjectYAML/ObjectYAML.cpp
+++ lib/ObjectYAML/ObjectYAML.cpp
@@ -33,6 +33,10 @@
       MappingTraits<MachOYAML::UniversalBinary>::mapping(IO,
                                                          *ObjectFile.FatMachO);
   } else {
+    // Nothing to parse, return.
+    if (!((Input &)IO).getCurrentNode())
+      return;
+
     if (IO.mapTag("!ELF")) {
       ObjectFile.Elf.reset(new ELFYAML::Object());
       MappingTraits<ELFYAML::Object>::mapping(IO, *ObjectFile.Elf);
Index: test/Object/yaml2obj-invalid.yaml
===================================================================
--- test/Object/yaml2obj-invalid.yaml
+++ test/Object/yaml2obj-invalid.yaml
@@ -0,0 +1,2 @@
+# RUN: not yaml2obj %s 2>&1 | FileCheck %s
+# CHECK: Unknown document type!