Index: llvm/trunk/test/tools/llvm-cvtres/symbols.test
===================================================================
--- llvm/trunk/test/tools/llvm-cvtres/symbols.test
+++ llvm/trunk/test/tools/llvm-cvtres/symbols.test
@@ -10,6 +10,10 @@
 RUN: llvm-cvtres /verbose /out:%t %p/Inputs/test_resource.res
 RUN: llvm-readobj -symbols %t | FileCheck %s
 
+// Test that parameters can be preceded by '-' in addition to '/':
+RUN: llvm-cvtres -verbose -machine:X86 -out:%t %p/Inputs/test_resource.res
+RUN: llvm-readobj -symbols %t | FileCheck %s
+
 CHECK:        Name: $R000000
 CHECK-NEXT:    Value: 0
 CHECK-NEXT:    Section: .rsrc$02
Index: llvm/trunk/tools/llvm-cvtres/Opts.td
===================================================================
--- llvm/trunk/tools/llvm-cvtres/Opts.td
+++ llvm/trunk/tools/llvm-cvtres/Opts.td
@@ -1,11 +1,13 @@
 include "llvm/Option/OptParser.td"
 
-def DEFINE : Joined<["/"], "DEFINE:">, HelpText<"">, MetaVarName<"symbol">;
-def FOLDDUPS : Flag<["/"], "FOLDDUPS:">, HelpText<"">;
-def MACHINE : Joined<["/"], "MACHINE:">, HelpText<"">, MetaVarName<"{ARM|ARM64|EBC|IA64|X64|X86}">;
-def NOLOGO : Flag<["/"], "NOLOGO">, HelpText<"">;
-def OUT : Joined<["/"], "OUT:">, HelpText<"">, MetaVarName<"filename">;
-def READONLY : Flag<["/"], "READONLY">, HelpText<"">;
-def VERBOSE : Flag<["/"], "VERBOSE">, HelpText<"">;
-def HELP : Flag<["/"], "HELP">;
-def H : Flag<["/"], "H">, Alias<HELP>;
+// All the switches can be preceded by either '/' or '-'.
+
+def DEFINE : Joined<["/", "-"], "DEFINE:">, HelpText<"">, MetaVarName<"symbol">;
+def FOLDDUPS : Flag<["/", "-"], "FOLDDUPS:">, HelpText<"">;
+def MACHINE : Joined<["/", "-"], "MACHINE:">, HelpText<"">, MetaVarName<"{ARM|ARM64|EBC|IA64|X64|X86}">;
+def NOLOGO : Flag<["/", "-"], "NOLOGO">, HelpText<"">;
+def OUT : Joined<["/", "-"], "OUT:">, HelpText<"">, MetaVarName<"filename">;
+def READONLY : Flag<["/", "-"], "READONLY">, HelpText<"">;
+def VERBOSE : Flag<["/", "-"], "VERBOSE">, HelpText<"">;
+def HELP : Flag<["/", "-"], "HELP">;
+def H : Flag<["/", "-"], "H">, Alias<HELP>;