Index: projects/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp
===================================================================
--- projects/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp
+++ projects/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp
@@ -16,10 +16,8 @@
 
 // string grouping() const;
 
-// TODO: investigation needed
-// XFAIL: linux-gnu
-
 #include <locale>
+#include <clocale>
 #include <cassert>
 
 #include "platform_support.h" // locale name macros
@@ -40,29 +38,37 @@
         }
     }
     {
+        assert(std::setlocale(LC_NUMERIC, LOCALE_en_US_UTF_8) != NULL);
+        char *expected = strdup(std::localeconv()->grouping);
+        assert(std::setlocale(LC_NUMERIC, "C") != NULL);
         std::locale l(LOCALE_en_US_UTF_8);
         {
             typedef char C;
             const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
-            assert(np.grouping() == "\3\3");
+            assert(np.grouping() == expected);
         }
         {
             typedef wchar_t C;
             const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
-            assert(np.grouping() == "\3\3");
+            assert(np.grouping() == expected);
         }
+        free(expected);
     }
     {
+        assert(std::setlocale(LC_NUMERIC, LOCALE_fr_FR_UTF_8) != NULL);
+        char *expected = strdup(std::localeconv()->grouping);
+        assert(std::setlocale(LC_NUMERIC, "C") != NULL);
         std::locale l(LOCALE_fr_FR_UTF_8);
         {
             typedef char C;
             const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
-            assert(np.grouping() == "\x7F");
+            assert(np.grouping() == expected);
         }
         {
             typedef wchar_t C;
             const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
-            assert(np.grouping() == "\x7F");
+            assert(np.grouping() == expected);
         }
+        free(expected);
     }
 }
Index: projects/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp
===================================================================
--- projects/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp
+++ projects/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp
@@ -16,10 +16,8 @@
 
 // char_type thousands_sep() const;
 
-// TODO: investigation needed
-// XFAIL: linux-gnu
-
 #include <locale>
+#include <clocale>
 #include <cassert>
 
 #include "platform_support.h" // locale name macros
@@ -40,29 +38,45 @@
         }
     }
     {
+        char expected;
+        wchar_t wexpected;
+        assert(std::setlocale(LC_ALL, LOCALE_en_US_UTF_8) != NULL);
+        const char *ts = std::localeconv()->thousands_sep;
+        expected = *ts;
+        int nb = mbtowc(&wexpected, ts, strlen(ts)+1);
+        assert(nb >= 0);
+        assert(std::setlocale(LC_ALL, "C") != NULL);
         std::locale l(LOCALE_en_US_UTF_8);
         {
             typedef char C;
             const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
-            assert(np.thousands_sep() == ',');
+            assert(np.thousands_sep() == expected);
         }
         {
             typedef wchar_t C;
             const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
-            assert(np.thousands_sep() == L',');
+            assert(np.thousands_sep() == wexpected);
         }
     }
     {
+        char expected;
+        wchar_t wexpected;
+        assert(std::setlocale(LC_ALL, LOCALE_fr_FR_UTF_8) != NULL);
+        const char *ts = std::localeconv()->thousands_sep;
+        expected = *ts;
+        int nb = mbtowc(&wexpected, ts, strlen(ts)+1);
+        assert(nb >= 0);
+        assert(std::setlocale(LC_ALL, "C") != NULL);
         std::locale l(LOCALE_fr_FR_UTF_8);
         {
             typedef char C;
             const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
-            assert(np.thousands_sep() == ',');
+            assert(np.thousands_sep() == expected);
         }
         {
             typedef wchar_t C;
             const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
-            assert(np.thousands_sep() == L',');
+            assert(np.thousands_sep() == wexpected);
         }
     }
 }