diff --git a/llvm/tools/llvm-objdump/llvm-objdump.cpp b/llvm/tools/llvm-objdump/llvm-objdump.cpp
index 7a3d0e2..d93e477 100644
--- a/llvm/tools/llvm-objdump/llvm-objdump.cpp
+++ b/llvm/tools/llvm-objdump/llvm-objdump.cpp
@@ -166,7 +166,7 @@
       // TheTriple defaults to ELF, and COFF doesn't have an environment:
       // the best we can do here is indicate that it is mach-o.
       if (Obj->isMachO())
-        TheTriple.setEnvironment(Triple::MachO);
+        TheTriple.setObjectFormat(Triple::MachO);
     }
   } else
     TheTriple.setTriple(Triple::normalize(TripleName));