Index: MinGW/Options.td
===================================================================
--- MinGW/Options.td
+++ MinGW/Options.td
@@ -54,6 +54,11 @@
 def require_defined: S<"require-defined">,
     HelpText<"Force symbol to be added to symbol table as an undefined one">;
 def require_defined_eq: J<"require-defined=">, Alias<require_defined>;
+// Strictly taken, the -u option allows for the symbol to remain undefined,
+// which this currently doesn't.
+def undefined: S<"u">, Alias<require_defined>;
+def undefined_long: S<"undefined">, Alias<require_defined>;
+def undefined_eq: J<"undefined=">, Alias<require_defined>;
 
 // LLD specific options
 def _HASH_HASH_HASH : Flag<["-"], "###">,
Index: test/MinGW/driver.test
===================================================================
--- test/MinGW/driver.test
+++ test/MinGW/driver.test
@@ -155,6 +155,7 @@
 MAP: -lldmap:bar.map
 
 RUN: ld.lld -### foo.o -m i386pe -require-defined _foo --require-defined _bar -require-defined=_baz --require-defined=_foo2 | FileCheck -check-prefix=REQUIRE-DEFINED %s
+RUN: ld.lld -### foo.o -m i386pe -u _foo --undefined _bar -undefined=_baz --undefined=_foo2 | FileCheck -check-prefix=REQUIRE-DEFINED %s
 REQUIRE-DEFINED: -include:_foo -include:_bar -include:_baz -include:_foo2
 
 RUN: ld.lld -### -m i386pep foo.o -Llibpath | FileCheck -check-prefix LIBPATH %s