diff --git a/llvm/test/tools/llvm-objdump/long-option-style.test b/llvm/test/tools/llvm-objdump/long-option-style.test
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-objdump/long-option-style.test
@@ -0,0 +1,18 @@
+## Don't make symlinks on Windows.
+# UNSUPPORTED: system-windows
+
+# RUN: rm -rf %t
+# RUN: mkdir %t
+# RUN: ln -s llvm-objdump %t/otool
+
+# RUN: llvm-objdump --help | FileCheck --check-prefix=LLVM-OBJDUMP %s
+# RUN: not llvm-objdump -help 2>&1 | FileCheck --check-prefix=UNKNOWN %s
+
+# LLVM-OBJDUMP: USAGE: llvm-objdump
+
+# UNKNOWN: llvm-objdump: Unknown command line argument '-help'.
+
+# RUN: %t/otool -help | FileCheck --check-prefix=OTOOL %s
+# RUN: %t/otool --help | FileCheck --check-prefix=OTOOL %s
+
+# OTOOL: USAGE: otool
diff --git a/llvm/tools/llvm-objdump/llvm-objdump.cpp b/llvm/tools/llvm-objdump/llvm-objdump.cpp
--- a/llvm/tools/llvm-objdump/llvm-objdump.cpp
+++ b/llvm/tools/llvm-objdump/llvm-objdump.cpp
@@ -2339,9 +2339,11 @@
   // Register the target printer for --version.
   cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
 
+  // In otool mode, support
+  bool LongOptionsUseDoubleDash =
+      StringRef(argv[0]).find("otool") == std::string::npos;
   cl::ParseCommandLineOptions(argc, argv, "llvm object file dumper\n", nullptr,
-                              /*EnvVar=*/nullptr,
-                              /*LongOptionsUseDoubleDash=*/true);
+                              /*EnvVar=*/nullptr, LongOptionsUseDoubleDash);
 
   if (StartAddress >= StopAddress)
     reportCmdLineError("start address should be less than stop address");