diff --git a/include/clang/Driver/CLCompatOptions.td b/include/clang/Driver/CLCompatOptions.td
index ed4c7e0f8c217f2044078d6243a0ae474b61e6ea..a520046d45bcb5278303cb626431cdba7b0587eb 100644
--- a/include/clang/Driver/CLCompatOptions.td
+++ b/include/clang/Driver/CLCompatOptions.td
@@ -122,6 +122,7 @@ def _SLASH_errorReport : CLIgnoredJoined<"errorReport">;
 def _SLASH_nologo : CLIgnoredFlag<"nologo">;
 def _SLASH_Ob1 : CLIgnoredFlag<"Ob1">;
 def _SLASH_Ob2 : CLIgnoredFlag<"Ob2">;
+def _SLASH_RTC : CLIgnoredJoined<"RTC">;
 def _SLASH_Zc_forScope : CLIgnoredFlag<"Zc:forScope">;
 def _SLASH_Zc_wchar_t : CLIgnoredFlag<"Zc:wchar_t">;
 def _SLASH_wd : CLIgnoredJoined<"wd">;
@@ -142,7 +143,6 @@ def _SLASH_Gy : CLFlag<"Gy">;
 def _SLASH_Gy_ : CLFlag<"Gy-">;
 def _SLASH_GZ : CLFlag<"GZ">;
 def _SLASH_MP : CLJoined<"MP">;
-def _SLASH_RTC : CLJoined<"RTC">;
 def _SLASH_w : CLJoined<"w">;
 def _SLASH_Za : CLFlag<"Za">;
 def _SLASH_Zc : CLJoined<"Zc:">;
diff --git a/test/Driver/cl-options.c b/test/Driver/cl-options.c
index 5387d2fa57c2617bac1a305c2ecd10e9efe7e68e..dc33db61b5af2ee2ffe9bdc138412ff367f97995 100644
--- a/test/Driver/cl-options.c
+++ b/test/Driver/cl-options.c
@@ -96,7 +96,7 @@
 // Ignored options. Check that we don't get "unused during compilation" errors.
 // (/Zs is for syntax-only, /WX is for -Werror)
 // RUN: %clang_cl /Zs /WX /analyze- /errorReport:foo /nologo /Ob1 /Ob2 -- %s
-// RUN: %clang_cl /Zs /WX /Zc:forScope /Zc:wchar_t /wd1234 -- %s
+// RUN: %clang_cl /Zs /WX /Zc:forScope /Zc:wchar_t /wd1234 /RTC1 -- %s
 
 // Support ignoring warnings about unused arguments.
 // RUN: %clang_cl /Abracadabra -Qunused-arguments -### -- %s 2>&1 | FileCheck -check-prefix=UNUSED %s
@@ -107,7 +107,7 @@
 // (/Zs is for syntax-only)
 // RUN: %clang_cl /Zs /EHsc /Fdfoo /fp:precise /Gd /GL /GL- -- %s 2>&1
 // RUN: %clang_cl /Zs /Gm /Gm- /GS /Gy /Gy- /GZ -- %s 2>&1
-// RUN: %clang_cl /Zs /RTC1 /wfoo /Zc:wchar_t- -- %s 2>&1
+// RUN: %clang_cl /Zs /wfoo /Zc:wchar_t- -- %s 2>&1
 // RUN: %clang_cl /Zs /ZI /Zi /MP -- %s 2>&1