diff --git a/lld/MinGW/Options.td b/lld/MinGW/Options.td
--- a/lld/MinGW/Options.td
+++ b/lld/MinGW/Options.td
@@ -85,7 +85,7 @@
 defm section_alignment: Eq<"section-alignment", "Set section alignment">;
 def shared: F<"shared">, HelpText<"Build a shared object">;
 defm subs: Eq<"subsystem", "Specify subsystem">;
-def stack: S<"stack">;
+defm stack: Eq<"stack", "Set size of the initial stack">;
 def strip_all: F<"strip-all">,
     HelpText<"Omit all symbol information from the output binary">;
 def strip_debug: F<"strip-debug">,
diff --git a/lld/test/MinGW/driver.test b/lld/test/MinGW/driver.test
--- a/lld/test/MinGW/driver.test
+++ b/lld/test/MinGW/driver.test
@@ -88,6 +88,7 @@
 
 RUN: ld.lld -### foo.o -m i386pep -stack 4194304,8192 2>&1 | FileCheck -check-prefix=STACK %s
 RUN: ld.lld -### foo.o -m i386pep --stack 4194304,8192 2>&1 | FileCheck -check-prefix=STACK %s
+RUN: ld.lld -### foo.o -m i386pep --stack=4194304,8192 2>&1 | FileCheck -check-prefix=STACK %s
 STACK: -stack:4194304,8192
 
 RUN: ld.lld -### foo.o -m i386pep -verbose 2>&1 | FileCheck -check-prefix=VERBOSE %s