diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 4981462ccc962a128089679d21a39279fa5d00fb..e4f70ceeef0218ee73ed5ac5bdc482bb996b47ce 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2013-02-13  Ed Smith-Rowland  <3dw4rd@verizon.net>
+
+	PR c++/55582
+	* g++.dg/cpp0x/udlit-string-literal.h: New.
+	* g++.dg/cpp0x/udlit-string-literal.C: New.
+
 2013-02-13  Sriraman Tallam  <tmsriram@google.com>
 
 	* g++.dg/ext/mv12-aux.C: Add directives to match mv12.C.
diff --git a/gcc/testsuite/g++.dg/cpp0x/udlit-string-literal.C b/gcc/testsuite/g++.dg/cpp0x/udlit-string-literal.C
new file mode 100644
index 0000000000000000000000000000000000000000..f83bef68ad33f2114b5e3269cf3e338e7b99bba5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/udlit-string-literal.C
@@ -0,0 +1,13 @@
+// { dg-options "-std=c++11" }
+// { dg-require-effective-target stdint_types }
+// PR c++/55582
+
+#include "udlit-string-literal.h"
+
+using namespace my_string_literals;
+
+decltype("Hello, World!"s) s;
+decltype(u8"Hello, World!"s) s8;
+decltype(L"Hello, World!"s) ws;
+decltype(u"Hello, World!"s) s16;
+decltype(U"Hello, World!"s) s32;
diff --git a/gcc/testsuite/g++.dg/cpp0x/udlit-string-literal.h b/gcc/testsuite/g++.dg/cpp0x/udlit-string-literal.h
new file mode 100644
index 0000000000000000000000000000000000000000..e61034ec4ef5e807f816ee2fa69b150b708253ec
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/udlit-string-literal.h
@@ -0,0 +1,22 @@
+#pragma GCC system_header
+
+#include <string>
+
+inline namespace my_string_literals
+{
+  std::string
+  operator"" s(const char* str, std::size_t len)
+  { return std::string{str, len}; }
+
+  std::wstring
+  operator"" s(const wchar_t* str, std::size_t len)
+  { return std::wstring{str, len}; }
+
+  std::u16string
+  operator"" s(const char16_t* str, std::size_t len)
+  { return std::u16string{str, len}; }
+
+  std::u32string
+  operator"" s(const char32_t* str, std::size_t len)
+  { return std::u32string{str, len}; }
+}
diff --git a/libcpp/ChangeLog b/libcpp/ChangeLog
index aa6a02d91f9cc59640913d8a0fbb3f364e989c18..22451a2103f71dbbf284c748b13f815304bdde90 100644
--- a/libcpp/ChangeLog
+++ b/libcpp/ChangeLog
@@ -1,3 +1,9 @@
+2013-02-13  Ed Smith-Rowland  <3dw4rd@verizon.net>
+
+	PR c++/55582
+	* libcpp/lex.c (lex_raw_string): Allow string literal with suffix
+	beginning with 's' to be parsed as a C++11 user-defined literal.
+
 2013-01-14  Richard Sandiford  <rdsandiford@googlemail.com>
 
 	Update copyright years.
diff --git a/libcpp/lex.c b/libcpp/lex.c
index aa87da95323149fc0d516d02bda3d7dbdbb9daac..976d9e8b0eb72f761ee394112ecc9de704276ab6 100644
--- a/libcpp/lex.c
+++ b/libcpp/lex.c
@@ -1561,8 +1561,10 @@ lex_raw_string (cpp_reader *pfile, cpp_token *token, const uchar *base,
 	 from inttypes.h, we generate a warning and treat the ud-suffix as a
 	 separate preprocessing token.  This approach is under discussion by
 	 the standards committee, and has been adopted as a conforming
-	 extension by other front ends such as clang. */
-      if (ISALPHA (*cur))
+	 extension by other front ends such as clang.
+         A special exception is made for the suffix 's' which will be
+	 standardized as a user-defined literal suffix for strings.  */
+      if (ISALPHA (*cur) && *cur != 's')
 	{
 	  /* Raise a warning, but do not consume subsequent tokens.  */
 	  if (CPP_OPTION (pfile, warn_literal_suffix))
@@ -1572,7 +1574,7 @@ lex_raw_string (cpp_reader *pfile, cpp_token *token, const uchar *base,
 				   "a space between literal and identifier");
 	}
       /* Grab user defined literal suffix.  */
-      else if (*cur == '_')
+      else if (ISIDST (*cur))
 	{
 	  type = cpp_userdef_string_add_type (type);
 	  ++cur;
@@ -1692,8 +1694,10 @@ lex_string (cpp_reader *pfile, cpp_token *token, const uchar *base)
 	 from inttypes.h, we generate a warning and treat the ud-suffix as a
 	 separate preprocessing token.  This approach is under discussion by
 	 the standards committee, and has been adopted as a conforming
-	 extension by other front ends such as clang. */
-      if (ISALPHA (*cur))
+	 extension by other front ends such as clang.
+         A special exception is made for the suffix 's' which will be
+	 standardized as a user-defined literal suffix for strings.  */
+      if (ISALPHA (*cur) && *cur != 's')
 	{
 	  /* Raise a warning, but do not consume subsequent tokens.  */
 	  if (CPP_OPTION (pfile, warn_literal_suffix))
@@ -1703,7 +1707,7 @@ lex_string (cpp_reader *pfile, cpp_token *token, const uchar *base)
 				   "a space between literal and identifier");
 	}
       /* Grab user defined literal suffix.  */
-      else if (*cur == '_')
+      else if (ISIDST (*cur))
 	{
 	  type = cpp_userdef_char_add_type (type);
 	  type = cpp_userdef_string_add_type (type);