Index: test/std/input.output/file.streams/fstreams/filebuf.virtuals/overflow.pass.cpp
===================================================================
--- test/std/input.output/file.streams/fstreams/filebuf.virtuals/overflow.pass.cpp
+++ test/std/input.output/file.streams/fstreams/filebuf.virtuals/overflow.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <fstream>
 
 // int_type overflow(int_type c = traits::eof());
Index: test/std/input.output/file.streams/fstreams/filebuf.virtuals/underflow.pass.cpp
===================================================================
--- test/std/input.output/file.streams/fstreams/filebuf.virtuals/underflow.pass.cpp
+++ test/std/input.output/file.streams/fstreams/filebuf.virtuals/underflow.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <fstream>
 
 // int_type underflow();
Index: test/std/input.output/iostream.format/ext.manip/get_time.pass.cpp
===================================================================
--- test/std/input.output/iostream.format/ext.manip/get_time.pass.cpp
+++ test/std/input.output/iostream.format/ext.manip/get_time.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <iomanip>
 
 // template <class charT> T9 get_time(struct tm* tmb, const charT* fmt);
Index: test/std/input.output/iostream.format/ext.manip/put_time.pass.cpp
===================================================================
--- test/std/input.output/iostream.format/ext.manip/put_time.pass.cpp
+++ test/std/input.output/iostream.format/ext.manip/put_time.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <iomanip>
 
 // template <class charT> T10 put_time(const struct tm* tmb, const charT* fmt);
Index: test/std/input.output/iostreams.base/ios.base/ios.base.callback/register_callback.pass.cpp
===================================================================
--- test/std/input.output/iostreams.base/ios.base/ios.base.callback/register_callback.pass.cpp
+++ test/std/input.output/iostreams.base/ios.base/ios.base.callback/register_callback.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <ios>
 
 // class ios_base
Index: test/std/input.output/iostreams.base/ios.base/ios.base.locales/imbue.pass.cpp
===================================================================
--- test/std/input.output/iostreams.base/ios.base/ios.base.locales/imbue.pass.cpp
+++ test/std/input.output/iostreams.base/ios.base/ios.base.locales/imbue.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <ios>
 
 // class ios_base
Index: test/std/input.output/iostreams.base/ios/basic.ios.members/imbue.pass.cpp
===================================================================
--- test/std/input.output/iostreams.base/ios/basic.ios.members/imbue.pass.cpp
+++ test/std/input.output/iostreams.base/ios/basic.ios.members/imbue.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <ios>
 
 // template <class charT, class traits> class basic_ios
Index: test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.pass.cpp
===================================================================
--- test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.pass.cpp
+++ test/std/input.output/stream.buffers/streambuf/streambuf.cons/copy.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <streambuf>
 
 // template <class charT, class traits = char_traits<charT> >
Index: test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.pass.cpp
===================================================================
--- test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.pass.cpp
+++ test/std/input.output/stream.buffers/streambuf/streambuf.cons/default.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <streambuf>
 
 // template <class charT, class traits = char_traits<charT> >
Index: test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/assign.pass.cpp
===================================================================
--- test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/assign.pass.cpp
+++ test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/assign.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <streambuf>
 
 // template <class charT, class traits = char_traits<charT> >
Index: test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/swap.pass.cpp
===================================================================
--- test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/swap.pass.cpp
+++ test/std/input.output/stream.buffers/streambuf/streambuf.protected/streambuf.assign/swap.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <streambuf>
 
 // template <class charT, class traits = char_traits<charT> >
Index: test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp
===================================================================
--- test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp
+++ test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <locale>
 
 // template <class charT> class collate_byname
Index: test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp
===================================================================
--- test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp
+++ test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <locale>
 
 // template <class charT>
Index: test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp
===================================================================
--- test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp
+++ test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <locale>
 
 // template <> class codecvt_byname<wchar_t, char, mbstate_t>
Index: test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp
===================================================================
--- test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp
+++ test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <locale>
 
 // template <class CharT>
Index: test/std/localization/locales/locale/locale.cons/default.pass.cpp
===================================================================
--- test/std/localization/locales/locale/locale.cons/default.pass.cpp
+++ test/std/localization/locales/locale/locale.cons/default.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <locale>
 
 // locale() throw();
Index: test/std/localization/locales/locale/locale.members/name.pass.cpp
===================================================================
--- test/std/localization/locales/locale/locale.members/name.pass.cpp
+++ test/std/localization/locales/locale/locale.members/name.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <locale>
 
 // basic_string<char> name() const;
Index: test/std/localization/locales/locale/locale.operators/eq.pass.cpp
===================================================================
--- test/std/localization/locales/locale/locale.operators/eq.pass.cpp
+++ test/std/localization/locales/locale/locale.operators/eq.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <locale>
 
 // basic_string<char> name() const;
Index: test/std/localization/locales/locale/locale.statics/global.pass.cpp
===================================================================
--- test/std/localization/locales/locale/locale.statics/global.pass.cpp
+++ test/std/localization/locales/locale/locale.statics/global.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <locale>
 
 // static const locale& classic();
Index: test/std/re/re.regex/re.regex.locale/imbue.pass.cpp
===================================================================
--- test/std/re/re.regex/re.regex.locale/imbue.pass.cpp
+++ test/std/re/re.regex/re.regex.locale/imbue.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <regex>
 
 // template <class charT, class traits = regex_traits<charT>> class basic_regex;
Index: test/std/re/re.traits/default.pass.cpp
===================================================================
--- test/std/re/re.traits/default.pass.cpp
+++ test/std/re/re.traits/default.pass.cpp
@@ -8,6 +8,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <regex>
 
 // template <class charT> struct regex_traits;
Index: test/std/re/re.traits/getloc.pass.cpp
===================================================================
--- test/std/re/re.traits/getloc.pass.cpp
+++ test/std/re/re.traits/getloc.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <regex>
 
 // template <class charT> struct regex_traits;
Index: test/std/re/re.traits/imbue.pass.cpp
===================================================================
--- test/std/re/re.traits/imbue.pass.cpp
+++ test/std/re/re.traits/imbue.pass.cpp
@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+// REQUIRES: locale.en_US.UTF-8
+
 // <regex>
 
 // template <class charT> struct regex_traits;