diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 8fd82e7ab66..8eb14808095 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,11 @@
+2012-10-01  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR libstdc++/54757
+	* include/ext/random (rice_distribution<>::operator()): Use std::hypot
+	only if _GLIBCXX_USE_C99_MATH_TR1.
+	* include/ext/random.tcc (rice_distribution<>::__generate_impl):
+	Likewise.
+
 2012-10-01  Daniel Krugler  <daniel.kruegler@googlemail.com>
 
 	* include/std/type_traits (result_of): Provide "SFINAE-friendly"
diff --git a/libstdc++-v3/include/ext/random b/libstdc++-v3/include/ext/random
index 884e8a0ca91..8c40d6d420a 100644
--- a/libstdc++-v3/include/ext/random
+++ b/libstdc++-v3/include/ext/random
@@ -1042,7 +1042,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	{
 	  result_type __x = this->_M_ndx(__urng);
 	  result_type __y = this->_M_ndy(__urng);
+#if _GLIBCXX_USE_C99_MATH_TR1
 	  return std::hypot(__x, __y);
+#else
+	  return std::sqrt(__x * __x + __y * __y);
+#endif
 	}
 
       template<typename _UniformRandomNumberGenerator>
@@ -1054,7 +1058,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	    __px(__p.nu(), __p.sigma()), __py(result_type(0), __p.sigma());
 	  result_type __x = this->_M_ndx(__px, __urng);
 	  result_type __y = this->_M_ndy(__py, __urng);
+#if _GLIBCXX_USE_C99_MATH_TR1
 	  return std::hypot(__x, __y);
+#else
+	  return std::sqrt(__x * __x + __y * __y);
+#endif
 	}
 
       template<typename _ForwardIterator,
diff --git a/libstdc++-v3/include/ext/random.tcc b/libstdc++-v3/include/ext/random.tcc
index 86bb67fedf9..4151daff83d 100644
--- a/libstdc++-v3/include/ext/random.tcc
+++ b/libstdc++-v3/include/ext/random.tcc
@@ -732,7 +732,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	      __px(__p.nu(), __p.sigma()), __py(result_type(0), __p.sigma());
 	    result_type __x = this->_M_ndx(__px, __urng);
 	    result_type __y = this->_M_ndy(__py, __urng);
+#if _GLIBCXX_USE_C99_MATH_TR1
 	    *__f++ = std::hypot(__x, __y);
+#else
+	    *__f++ = std::sqrt(__x * __x + __y * __y);
+#endif
 	  }
       }