diff --git a/include/boost/regex/v4/regex_traits_defaults.hpp b/include/boost/regex/v4/regex_traits_defaults.hpp
index 2a2cf21d..d5107882 100644
--- a/include/boost/regex/v4/regex_traits_defaults.hpp
+++ b/include/boost/regex/v4/regex_traits_defaults.hpp
@@ -330,11 +330,11 @@ inline const charT* get_escape_R_string()
 #  pragma warning(push)
 #  pragma warning(disable:4309 4245)
 #endif
-   static const charT e1[] = { '(', '?', '>', '\x0D', '\x0A', '?',
-      '|', '[', '\x0A', '\x0B', '\x0C', static_cast<unsigned char>('\x85'), '\\', 'x', '{', '2', '0', '2', '8', '}',
+   static const charT e1[] = { '(', '?', '>', '\\', 'x', '0', 'D', '\\', 'x', '0', 'A', '?',
+      '|', '[', '\\', 'x', '0', 'A', '\\', 'x', '0', 'B', '\\', 'x', '0', 'C', static_cast<unsigned char>('\x85'), '\\', 'x', '{', '2', '0', '2', '8', '}',
                 '\\', 'x', '{', '2', '0', '2', '9', '}', ']', ')', '\0' };
-   static const charT e2[] = { '(', '?', '>', '\x0D', '\x0A', '?',
-      '|', '[', '\x0A', '\x0B', '\x0C', static_cast<unsigned char>('\x85'), ']', ')', '\0' };
+   static const charT e2[] = { '(', '?', '>', '\\', 'x', '0', 'D', '\\', 'x', '0', 'A', '?',
+      '|', '[', '\\', 'x', '0', 'A', '\\', 'x', '0', 'B', '\\', 'x', '0', 'C', static_cast<unsigned char>('\x85'), ']', ')', '\0' };
 
    charT c = static_cast<charT>(0x2029u);
    bool b = (static_cast<unsigned>(c) == 0x2029u);
@@ -352,8 +352,8 @@ inline const char* get_escape_R_string<char>()
 #  pragma warning(push)
 #  pragma warning(disable:4309)
 #endif
-   static const char e2[] = { '(', '?', '>', '\x0D', '\x0A', '?',
-      '|', '[', '\x0A', '\x0B', '\x0C', '\x85', ']', ')', '\0' };
+   static const char e2[] = { '(', '?', '>', '\\', 'x', '0', 'D', '\\', 'x', '0', 'A', '?',
+      '|', '[', '\\', 'x', '0', 'A', '\\', 'x', '0', 'B', '\\', 'x', '0', 'C', '\\', 'x', '8', '5', ']', ')', '\0' };
    return e2;
 #ifdef BOOST_MSVC
 #  pragma warning(pop)
diff --git a/test/regress/test_escapes.cpp b/test/regress/test_escapes.cpp
index e3d675be..567bf43a 100644
--- a/test/regress/test_escapes.cpp
+++ b/test/regress/test_escapes.cpp
@@ -155,12 +155,19 @@ void test_assertion_escapes()
    TEST_REGEX_SEARCH("\\R", perl, "foo\nbar", match_default, make_array(3, 4, -2, -2));
    TEST_REGEX_SEARCH("\\R", perl, "foo\rbar", match_default, make_array(3, 4, -2, -2));
    TEST_REGEX_SEARCH("\\R", perl, "foo\r\nbar", match_default, make_array(3, 5, -2, -2));
+   TEST_REGEX_SEARCH("(?x) abc \\R", perl, "abc\r\nbar", match_default, make_array(0, 5, -2, -2));
+   TEST_REGEX_SEARCH("(?x) abc \\R", perl, "abc\x0A" "bar", match_default, make_array(0, 4, -2, -2));
+   TEST_REGEX_SEARCH("(?x) abc \\R", perl, "abc\x0B" "bar", match_default, make_array(0, 4, -2, -2));
+   TEST_REGEX_SEARCH("(?x) abc \\R", perl, "abc\x0C" "bar", match_default, make_array(0, 4, -2, -2));
+   TEST_REGEX_SEARCH("(?x) abc \\R", perl, "abc\x85" "bar", match_default, make_array(0, 4, -2, -2));
    // see if \u works:
    const wchar_t* w = L"\u2028";
    if(*w == 0x2028u)
    {
       TEST_REGEX_SEARCH_W(L"\\R", perl, L"foo\u2028bar", match_default, make_array(3, 4, -2, -2));
       TEST_REGEX_SEARCH_W(L"\\R", perl, L"foo\u2029bar", match_default, make_array(3, 4, -2, -2));
+      TEST_REGEX_SEARCH_W(L"(?x) abc \\R", perl, L"abc\u2028bar", match_default, make_array(0, 4, -2, -2));
+      TEST_REGEX_SEARCH_W(L"(?x) abc \\R", perl, L"abc\u2029bar", match_default, make_array(0, 4, -2, -2));
    }
 }