diff --git a/llvm/lib/ObjectYAML/ELFYAML.cpp b/llvm/lib/ObjectYAML/ELFYAML.cpp
--- a/llvm/lib/ObjectYAML/ELFYAML.cpp
+++ b/llvm/lib/ObjectYAML/ELFYAML.cpp
@@ -586,6 +586,10 @@
   ECase(STT_COMMON);
   ECase(STT_TLS);
   ECase(STT_GNU_IFUNC);
+  ECase(STT_LOOS);
+  ECase(STT_HIOS);
+  ECase(STT_LOPROC);
+  ECase(STT_HIPROC);
 #undef ECase
   IO.enumFallback<Hex8>(Value);
 }