Index: test/tools/llvm-nm/X86/externalonly.test
===================================================================
--- test/tools/llvm-nm/X86/externalonly.test
+++ test/tools/llvm-nm/X86/externalonly.test
@@ -1,4 +1,5 @@
 # RUN: llvm-nm -g %p/Inputs/hello.obj.macho-x86_64 | FileCheck %s
+# RUN: llvm-nm -g -g %p/Inputs/hello.obj.macho-x86_64 | FileCheck %s
 
 # CHECK-NOT: EH_frame0
 # CHECK: _main
Index: tools/llvm-nm/llvm-nm.cpp
===================================================================
--- tools/llvm-nm/llvm-nm.cpp
+++ tools/llvm-nm/llvm-nm.cpp
@@ -85,9 +85,11 @@
                        cl::aliasopt(DefinedOnly), cl::Grouping);
 
 cl::opt<bool> ExternalOnly("extern-only",
-                           cl::desc("Show only external symbols"));
+                           cl::desc("Show only external symbols"),
+                           cl::ZeroOrMore);
 cl::alias ExternalOnly2("g", cl::desc("Alias for --extern-only"),
-                        cl::aliasopt(ExternalOnly), cl::Grouping);
+                        cl::aliasopt(ExternalOnly), cl::Grouping,
+                        cl::ZeroOrMore);
 
 cl::opt<bool> BSDFormat("B", cl::desc("Alias for --format=bsd"),
                         cl::Grouping);