diff --git a/libcxx/include/__config_site.in b/libcxx/include/__config_site.in
index fc01aaf2d8746..b68c0c8258366 100644
--- a/libcxx/include/__config_site.in
+++ b/libcxx/include/__config_site.in
@@ -30,7 +30,6 @@
 #cmakedefine01 _LIBCPP_HAS_LOCALIZATION
 #cmakedefine01 _LIBCPP_HAS_UNICODE
 #cmakedefine01 _LIBCPP_HAS_WIDE_CHARACTERS
-#cmakedefine _LIBCPP_HAS_NO_STD_MODULES
 #cmakedefine01 _LIBCPP_HAS_TIME_ZONE_DATABASE
 #cmakedefine01 _LIBCPP_INSTRUMENTED_WITH_ASAN
 
diff --git a/llvm/utils/gn/secondary/libcxx/include/BUILD.gn b/llvm/utils/gn/secondary/libcxx/include/BUILD.gn
index 6051674a790e8..f6473c672a050 100644
--- a/llvm/utils/gn/secondary/libcxx/include/BUILD.gn
+++ b/llvm/utils/gn/secondary/libcxx/include/BUILD.gn
@@ -35,7 +35,6 @@ if (current_toolchain == default_toolchain) {
       "_LIBCPP_HAS_LOCALIZATION=1",
       "_LIBCPP_HAS_UNICODE=1",
       "_LIBCPP_HAS_WIDE_CHARACTERS=1",
-      "_LIBCPP_HAS_NO_STD_MODULES=",
       "_LIBCPP_HAS_TERMINAL=1",
       "_LIBCPP_INSTRUMENTED_WITH_ASAN=",
       "_LIBCPP_ABI_DEFINES=",