diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_char8_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_char8_t_out.pass.cpp
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_char8_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_char8_t_out.pass.cpp
@@ -27,7 +27,7 @@
 int main(int, char**) {
   using F = std::codecvt<char16_t, char8_t, std::mbstate_t>;
   const F& f = std::use_facet<F>(std::locale::classic());
-  F::intern_type from[9] = {'s', 'o', 'm', 'e', ' ', 't', 'e', 'x', 't'};
+  F::intern_type from[9] = {u's', u'o', u'm', u'e', u' ', u't', u'e', u'x', u't'};
   F::extern_type to[9] = {0};
   std::mbstate_t mbs = {};
   const F::intern_type* from_next = nullptr;
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp
@@ -17,6 +17,8 @@
 // This test runs in C++20, but we have deprecated codecvt<char(16|32), char, mbstate_t> in C++20.
 // ADDITIONAL_COMPILE_FLAGS: -D_LIBCPP_DISABLE_DEPRECATION_WARNINGS
 
+// UNSUPPORTED: target={{.+}}-zos{{.*}}
+
 #include <locale>
 #include <string>
 #include <vector>
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_char8_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_char8_t_out.pass.cpp
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_char8_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_char8_t_out.pass.cpp
@@ -27,7 +27,7 @@
 int main(int, char**) {
   using F = std::codecvt<char32_t, char8_t, std::mbstate_t>;
   const F& f = std::use_facet<F>(std::locale::classic());
-  F::intern_type from[9] = {'s', 'o', 'm', 'e', ' ', 't', 'e', 'x', 't'};
+  F::intern_type from[9] = {u's', u'o', u'm', u'e', u' ', u't', u'e', u'x', u't'};
   F::extern_type to[9] = {0};
   std::mbstate_t mbs = {};
   const F::intern_type* from_next = nullptr;
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp
@@ -17,6 +17,8 @@
 // This test runs in C++20, but we have deprecated codecvt<char(16|32), char, mbstate_t> in C++20.
 // ADDITIONAL_COMPILE_FLAGS: -D_LIBCPP_DISABLE_DEPRECATION_WARNINGS
 
+// UNSUPPORTED: target={{.+}}-zos{{.*}}
+
 #include <locale>
 #include <string>
 #include <vector>