diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp
@@ -20,6 +20,7 @@
 
 #include <locale>
 #include <ios>
+#include <iostream>
 #include <streambuf>
 #include <cassert>
 #include "test_macros.h"
@@ -56,6 +57,15 @@
 
 int main(int, char**)
 {
+#if defined(_CS_GNU_LIBC_VERSION)
+    // Glibc before 2.27 used '.' instead of ',' as monetary decimal separator.
+    // Just skip the test (which gets marked as PASS, though) to avoid
+    // unnecessary churn for such old versions.
+    if (glibc_version_less_than("2.27")) {
+        std::cerr << "Skipping test\n";
+        return 0;
+    }
+#endif
     std::ios ios(0);
     std::string loc_name(LOCALE_ru_RU_UTF_8);
     ios.imbue(std::locale(ios.getloc(),
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp
@@ -20,6 +20,7 @@
 
 #include <locale>
 #include <ios>
+#include <iostream>
 #include <streambuf>
 #include <cassert>
 #include "test_macros.h"
@@ -56,6 +57,15 @@
 
 int main(int, char**)
 {
+#if defined(_CS_GNU_LIBC_VERSION)
+    // Glibc before 2.27 used '.' instead of ',' as monetary decimal separator.
+    // Just skip the test (which gets marked as PASS, though) to avoid
+    // unnecessary churn for such old versions.
+    if (glibc_version_less_than("2.27")) {
+        std::cerr << "Skipping test\n";
+        return 0;
+    }
+#endif
     std::ios ios(0);
     std::string loc_name(LOCALE_ru_RU_UTF_8);
     ios.imbue(std::locale(ios.getloc(),