re PR libstdc++/31426 (TR1 includes do not work with -std=c++0x)

2007-05-31  Paolo Carlini  <pcarlini@suse.de>

	PR libstdc++/31426
	* include/bits/c++config: Remove namespace association bits
	from tr1 to std.

	* include/ext/type_traits.h (__promote, __promote2,
	__promote3, __promote4): Add.

	* include/bits/hashtable.h: New.
	* include/bits/functional_hash.h: Likewise.
	* include/tr1/hashtable.h: Likewise.

	* include/tr1_impl/random: New.
	* include/tr1_impl/cinttypes: Likewise.
	* include/tr1_impl/cstdlib: Likewise.
	* include/tr1_impl/unordered_map: Likewise.
	* include/tr1_impl/cstdio: Likewise.
	* include/tr1_impl/boost_shared_ptr.h: Likewise.
	* include/tr1_impl/cctype: Likewise.
	* include/tr1_impl/random.tcc: Likewise.
	* include/tr1_impl/tuple: Likewise.
	* include/tr1_impl/functional_hash.h: Likewise.
	* include/tr1_impl/hashtable: Likewise.
	* include/tr1_impl/cmath: Likewise.
	* include/tr1_impl/type_traitsfwd.h: Likewise.
	* include/tr1_impl/hashtable_policy.h: Likewise.
	* include/tr1_impl/cfenv: Likewise.
	* include/tr1_impl/unordered_set: Likewise.
	* include/tr1_impl/functional: Likewise.
	* include/tr1_impl/utility: Likewise.
	* include/tr1_impl/complex: Likewise.
	* include/tr1_impl/type_traits: Likewise.
	* include/tr1_impl/cwchar: Likewise.
	* include/tr1_impl/cstdint: Likewise.
	* include/tr1_impl/regex: Likewise.
	* include/tr1_impl/array: Likewise.
	* include/tr1_impl/cwctype: Likewise.

	* include/tr1/type_traitsfwd.h: Remove.
	* include/tr1/boost_shared_ptr.h: Likewise.
	* include/tr1/common.h: Likewise.
	* include/tr1/hashtable: Likewise.
	* include/tr1/hashtable_policy.h: Likewise.
	* include/tr1/random.tcc: Likewise.

	* include/c_global/cinttypes: Include tr1_impl/cinttypes.
	* include/c_global/cstdlib: Likewise for cstdlib.
	* include/c_global/cstdio: Likewise for cstdio.
	* include/c_global/cctype: Likewise for cctype.
	* include/c_global/cmath: Likewise for cmath.
	* include/c_global/cfenv: Likewise for cfenv.
	* include/c_global/cwchar: Likewise for cwchar.
	* include/c_global/cstdint: Likewise for cstdint.
	* include/c_global/cwctype: Likewise for cwctype.
	* include/tr1/cinttypes: Likewise for cinttypes.
	* include/tr1/cstdlib: Likewise for cstdlib.
	* include/tr1/cstdio: Likewise for cstdio.
	* include/tr1/cctype: Likewise for cctype.
	* include/tr1/cmath: Likewise for cmath.
	* include/tr1/cfenv: Likewise for cfenv.
	* include/tr1/cwchar: Likewise for cwchar.
	* include/tr1/cstdint: Likewise for cstdint.
	* include/tr1/cwctype: Likewise for cwctype.
	* include/tr1/functional_hash.h: Likewise for functional_hash.

	* include/std/tuple: Include tr1_impl/tuple.
	* include/std/utility: Likewise for utility.
	* include/std/type_traits: Likewise for type_traits.
	(is_pod): Just forward to __is_pod.
	(has_trivial_default_constructor): Just forward to
	__has_trivial_constructor.
	(has_trivial_copy_constructor): Just forward to __has_trivial_copy.
	(has_trivial_assign): Just forward to __has_trivial_assign.
	(has_trivial_destructor): Just forward to __has_trivial_destructor.
	(has_nothrow_default_constructor): Just forward to
	__has_nothrow_constructor.
	(has_nothrow_copy_constructor): Just forward to __has_nothrow_copy.
	(has_nothrow_assign): Just forward to __has_nothrow_assign.
	(is_base_of): Just forward to __is_base_of.
	(is_signed, is_unsigned): Implement according to the C++0x
	specifications.
	* include/std/memory: Likewise for memory.
	* include/std/regex: Likewise for regex.
	* include/std/random: Likewise for random.
	* include/std/unordered_map: Likewise for unordered_map.
	* include/std/unordered_set: Likewise for unordered_set.
	* include/std/functional: Likewise for functional.
	* include/std/complex: Likewise for complex.
	* include/std/array: Likewise for array.
	* include/tr1/tuple: Likewise for tuple.
	* include/tr1/utility: Likewise for utility.
	* include/tr1/type_traits: Likewise for type_traits
	* include/tr1/memory: Likewise for memory.
	* include/tr1/regex: Likewise for regex.
	* include/tr1/random: Likewise for random.
	* include/tr1/unordered_map: Likewise for unordered_map.
	* include/tr1/unordered_set: Likewise for unordered_set.
	* include/tr1/functional: Likewise for functional.
	* include/tr1/complex: Likewise for complex.
	* include/tr1/array: Likewise for array.

	* include/c_global/ctgmath: Tweak.
	* include/c_global/cstdarg: Likewise.
	* include/c_global/ctime: Likewise.
	* include/c_global/climits: Likewise.
	* include/c_global/cfloat: Likewise.	
	* include/c_global/ccomplex: Likewise.
	* include/c_global/cstdbool: Likewise.

	* include/tr1/poly_laguerre.tcc: Tweak, don't use _GLIBCXX_TR1.
	* include/tr1/riemann_zeta.tcc: Likewise.
	* include/tr1/beta_function.tcc: Likewise.
	* include/tr1/exp_integral.tcc: Likewise.
	* include/tr1/hypergeometric.tcc: Likewise.
	* include/tr1/modified_bessel_func.tcc: Likewise.
	* include/tr1/legendre_function.tcc: Likewise.
	* include/tr1/special_function_util.h: Likewise.
	* include/tr1/bessel_function.tcc: Likewise.
	* include/tr1/poly_hermite.tcc: Likewise.
	* include/tr1/ell_integral.tcc: Likewise.
	* include/tr1/gamma.tcc: Likewise.
	* include/tr1/stdlib.h: Likewise.
	* include/tr1/math.h: Likewise.

	* include/tr1/complex.h: Minor tweaks.
	* include/tr1/wctype.h: Likewise.
	* include/tr1/wchar.h: Likewise.
	* include/tr1/inttypes.h: Likewise.
	* include/tr1/tgmath.h: Likewise.
	* include/tr1/cstdbool: Likewise.
	* include/tr1/cfloat: Likewise.
	* include/tr1/ccomplex: Likewise.
	* include/tr1/ctime: Likewise.
	* include/tr1/climits: Likewise.
	* include/tr1/ctgmath: Likewise.
	* include/tr1/cstdarg: Likewise.

	* testsuite/tr1/headers.cc: Move...
	* testsuite/tr1/headers/all.cc: ... here.
	* testsuite/tr1/using_namespace_std_tr1.cc: Move...
	* testsuite/tr1/headers/c++200x/using_namespace_std_tr1.cc: ... here.
	* testsuite/tr1/headers/using_namespace_std_tr1.cc ... here.
	* testsuite/tr1/headers/c++200x/using_namespace_std_tr1.cc: New.

	* testsuite/20_util/tuple/requirements/explicit_instantiation.cc:
	Adjust namespace.
	* testsuite/20_util/has_nothrow_copy_constructor/value.cc: Adjust to
	the C++0x requirements.
	* testsuite/20_util/has_nothrow_default_constructor/value.cc: Likewise.
	* testsuite/20_util/has_trivial_copy_constructor/value.cc: Likewise.
	* testsuite/20_util/has_trivial_default_constructor/value.cc: Likewise.

	* testsuite/20_util/make_signed/requirements/typedefs_neg.cc: Adjust
	dg-error lines.
	* testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc:
	Likewise.
	* testsuite/20_util/headers/type_traits/types_std_c++0x_neg.cc:
	Un-xfail.

	* testsuite/20_util/is_signed/value.cc: New.
	* testsuite/20_util/is_signed/requirements/typedefs.cc: Likewise.
	* testsuite/20_util/is_signed/requirements/explicit_instantiation.cc:
	Likewise.
	* testsuite/20_util/is_unsigned/value.cc: Likewise..
	* testsuite/20_util/is_unsigned/requirements/typedefs.cc: Likewise.
	* testsuite/20_util/is_unsigned/requirements/explicit_instantiation.cc:
	Likewise.

	* include/Makefile.am: Adjust.	
	* include/Makefile.in: Regenerate.

From-SVN: r125244

1 files changed, 22 insertions, 2317 deletions

diff --git a/libstdc++-v3/include/tr1/random b/libstdc++-v3/include/tr1/random
index 1033743..49a3b21 100644
--- a/libstdc++-v3/include/tr1/random
+++ b/libstdc++-v3/include/tr1/random
@@ -32,8 +32,14 @@
  * This is a TR1 C++ Library header. 
  */
 
-#ifndef _TR1_RANDOM
-#define _TR1_RANDOM 1
+#ifndef _GLIBCXX_TR1_RANDOM
+#define _GLIBCXX_TR1_RANDOM 1
+
+#pragma GCC system_header
+
+#if defined(_GLIBCXX_INCLUDE_AS_CXX0X)
+#  error TR1 header cannot be included from C++0x header
+#endif
 
 #include <cmath>
 #include <cstdio>
@@ -41,2326 +47,25 @@
 #include <string>
 #include <iosfwd>
 #include <limits>
-#include <tr1/type_traits>
-#include <tr1/cmath>
 #include <ext/type_traits.h>
 #include <ext/numeric_traits.h>
 #include <bits/concept_check.h>
 #include <debug/debug.h>
+#include <tr1/type_traits>
+#include <tr1/cmath>
 
-namespace std
-{
-_GLIBCXX_BEGIN_NAMESPACE(_GLIBCXX_TR1)
-
-  // [5.1] Random number generation
-
-  /**
-   * @addtogroup tr1_random Random Number Generation
-   * A facility for generating random numbers on selected distributions.
-   * @{
-   */
-
-  /*
-   * Implementation-space details.
-   */
-  namespace __detail
-  {
-    template<typename _UIntType, int __w, 
-	     bool = __w < std::numeric_limits<_UIntType>::digits>
-      struct _Shift
-      { static const _UIntType __value = 0; };
-
-    template<typename _UIntType, int __w>
-      struct _Shift<_UIntType, __w, true>
-      { static const _UIntType __value = _UIntType(1) << __w; };
-
-    template<typename _Tp, _Tp __a, _Tp __c, _Tp __m, bool>
-      struct _Mod;
-
-    // Dispatch based on modulus value to prevent divide-by-zero compile-time
-    // errors when m == 0.
-    template<typename _Tp, _Tp __a, _Tp __c, _Tp __m>
-      inline _Tp
-      __mod(_Tp __x)
-      { return _Mod<_Tp, __a, __c, __m, __m == 0>::__calc(__x); }
-
-    typedef __gnu_cxx::__conditional_type<(sizeof(unsigned) == 4),
-		    unsigned, unsigned long>::__type _UInt32Type;
-
-    /*
-     * An adaptor class for converting the output of any Generator into
-     * the input for a specific Distribution.
-     */
-    template<typename _Engine, typename _Distribution>
-      struct _Adaptor
-      { 
-	typedef typename _Engine::result_type        _Engine_result_type;
-	typedef typename _Distribution::input_type   result_type;
-
-      public:
-	_Adaptor(const _Engine& __g)
-	: _M_g(__g) { }
-
-	result_type
-	min() const
-	{
-	  result_type __return_value = 0;
-	  if (is_integral<_Engine_result_type>::value
-	      && is_integral<result_type>::value)
-	    __return_value = _M_g.min();
-	  else if (!is_integral<result_type>::value)
-	    __return_value = result_type(0);
-	  return __return_value;
-	}
-
-	result_type
-	max() const
-	{
-	  result_type __return_value = 0;
-	  if (is_integral<_Engine_result_type>::value
-	      && is_integral<result_type>::value)
-	    __return_value = _M_g.max();
-	  else if (!is_integral<result_type>::value)
-	    __return_value = result_type(1);
-	  return __return_value;
-	}
-
-	result_type
-	operator()();
-
-      private:
-	_Engine _M_g;
-      };
-
-    /*
-     * Converts a value generated by the adapted random number generator into a
-     * value in the input domain for the dependent random number distribution.
-     *
-     * Because the type traits are compile time constants only the appropriate
-     * clause of the if statements will actually be emitted by the compiler.
-     */
-    template<typename _Engine, typename _Distribution>
-      typename _Adaptor<_Engine, _Distribution>::result_type
-      _Adaptor<_Engine, _Distribution>::
-      operator()()
-      {
-	result_type __return_value = 0;
-	if (is_integral<_Engine_result_type>::value
-	    && is_integral<result_type>::value)
-	  __return_value = _M_g();
-      	else if (is_integral<_Engine_result_type>::value
-		 && !is_integral<result_type>::value)
-	  __return_value = result_type(_M_g() - _M_g.min())
-	    / result_type(_M_g.max() - _M_g.min() + result_type(1));
-	else if (!is_integral<_Engine_result_type>::value
-		 && !is_integral<result_type>::value)
-	  __return_value = result_type(_M_g() - _M_g.min())
-	    / result_type(_M_g.max() - _M_g.min());
-      	return __return_value;
-      }
-  } // namespace __detail
-
-  /**
-   * Produces random numbers on a given disribution function using a un uniform
-   * random number generation engine.
-   *
-   * @todo the engine_value_type needs to be studied more carefully.
-   */
-  template<typename _Engine, typename _Dist>
-    class variate_generator
-    {
-      // Concept requirements.
-      __glibcxx_class_requires(_Engine, _CopyConstructibleConcept)
-      //  __glibcxx_class_requires(_Engine, _EngineConcept)
-      //  __glibcxx_class_requires(_Dist, _EngineConcept)
-
-    public:
-      typedef _Engine                                engine_type;
-      typedef __detail::_Adaptor<_Engine, _Dist>     engine_value_type;
-      typedef _Dist                                  distribution_type;
-      typedef typename _Dist::result_type            result_type;
-
-      // tr1:5.1.1 table 5.1 requirement
-      typedef typename __gnu_cxx::__enable_if<
-	is_arithmetic<result_type>::value, result_type>::__type _IsValidType;
-
-      /**
-       * Constructs a variate generator with the uniform random number
-       * generator @p __eng for the random distribution @p __dist.
-       *
-       * @throws Any exceptions which may thrown by the copy constructors of
-       * the @p _Engine or @p _Dist objects.
-       */
-      variate_generator(engine_type __eng, distribution_type __dist)
-      : _M_engine(__eng), _M_dist(__dist) { }
-
-      /**
-       * Gets the next generated value on the distribution.
-       */
-      result_type
-      operator()()
-      { return _M_dist(_M_engine); }
-
-      /**
-       * WTF?
-       */
-      template<typename _Tp>
-        result_type
-        operator()(_Tp __value)
-        { return _M_dist(_M_engine, __value); }
-
-      /**
-       * Gets a reference to the underlying uniform random number generator
-       * object.
-       */
-      engine_value_type&
-      engine()
-      { return _M_engine; }
-
-      /**
-       * Gets a const reference to the underlying uniform random number
-       * generator object.
-       */
-      const engine_value_type&
-      engine() const
-      { return _M_engine; }
-
-      /**
-       * Gets a reference to the underlying random distribution.
-       */
-      distribution_type&
-      distribution()
-      { return _M_dist; }
-
-      /**
-       * Gets a const reference to the underlying random distribution.
-       */
-      const distribution_type&
-      distribution() const
-      { return _M_dist; }
-
-      /**
-       * Gets the closed lower bound of the distribution interval.
-       */
-      result_type
-      min() const
-      { return this->distribution().min(); }
-
-      /**
-       * Gets the closed upper bound of the distribution interval.
-       */
-      result_type
-      max() const
-      { return this->distribution().max(); }
-
-    private:
-      engine_value_type _M_engine;
-      distribution_type _M_dist;
-    };
-
-
-  /**
-   * @addtogroup tr1_random_generators Random Number Generators
-   * @ingroup tr1_random
-   *
-   * These classes define objects which provide random or pseudorandom
-   * numbers, either from a discrete or a continuous interval.  The
-   * random number generator supplied as a part of this library are
-   * all uniform random number generators which provide a sequence of
-   * random number uniformly distributed over their range.
-   *
-   * A number generator is a function object with an operator() that
-   * takes zero arguments and returns a number.
-   *
-   * A compliant random number generator must satisy the following
-   * requirements.  <table border=1 cellpadding=10 cellspacing=0>
-   * <caption align=top>Random Number Generator Requirements</caption>
-   * <tr><td>To be documented.</td></tr> </table>
-   * 
-   * @{
-   */
-
-  /**
-   * @brief A model of a linear congruential random number generator.
-   *
-   * A random number generator that produces pseudorandom numbers using the
-   * linear function @f$x_{i+1}\leftarrow(ax_{i} + c) \bmod m @f$.
-   *
-   * The template parameter @p _UIntType must be an unsigned integral type
-   * large enough to store values up to (__m-1). If the template parameter
-   * @p __m is 0, the modulus @p __m used is
-   * std::numeric_limits<_UIntType>::max() plus 1. Otherwise, the template
-   * parameters @p __a and @p __c must be less than @p __m.
-   *
-   * The size of the state is @f$ 1 @f$.
-   */
-  template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
-    class linear_congruential
-    {
-      __glibcxx_class_requires(_UIntType, _UnsignedIntegerConcept)
-      //  __glibcpp_class_requires(__a < __m && __c < __m)
-
-    public:
-      /** The type of the generated random value. */
-      typedef _UIntType result_type;
-
-      /** The multiplier. */
-      static const _UIntType multiplier = __a;
-      /** An increment. */
-      static const _UIntType increment = __c;
-      /** The modulus. */
-      static const _UIntType modulus = __m;
-
-      /**
-       * Constructs a %linear_congruential random number generator engine with
-       * seed @p __s.  The default seed value is 1.
-       *
-       * @param __s The initial seed value.
-       */
-      explicit
-      linear_congruential(unsigned long __x0 = 1)
-      { this->seed(__x0); }
-
-      /**
-       * Constructs a %linear_congruential random number generator engine
-       * seeded from the generator function @p __g.
-       *
-       * @param __g The seed generator function.
-       */
-      template<class _Gen>
-        linear_congruential(_Gen& __g)
-        { this->seed(__g); }
-
-      /**
-       * Reseeds the %linear_congruential random number generator engine
-       * sequence to the seed @g __s.
-       *
-       * @param __s The new seed.
-       */
-      void
-      seed(unsigned long __s = 1);
-
-      /**
-       * Reseeds the %linear_congruential random number generator engine
-       * sequence using values from the generator function @p __g.
-       *
-       * @param __g the seed generator function.
-       */
-      template<class _Gen>
-        void
-        seed(_Gen& __g)
-        { seed(__g, typename is_fundamental<_Gen>::type()); }
-
-      /**
-       * Gets the smallest possible value in the output range.
-       *
-       * The minumum depends on the @p __c parameter: if it is zero, the
-       * minimum generated must be > 0, otherwise 0 is allowed.
-       */
-      result_type
-      min() const
-      { return (__detail::__mod<_UIntType, 1, 0, __m>(__c) == 0) ? 1 : 0; }
-
-      /**
-       * Gets the largest possible value in the output range.
-       */
-      result_type
-      max() const
-      { return __m - 1; }
-
-      /**
-       * Gets the next random number in the sequence.
-       */
-      result_type
-      operator()();
-
-      /**
-       * Compares two linear congruential random number generator
-       * objects of the same type for equality.
-       *  
-       * @param __lhs A linear congruential random number generator object.
-       * @param __rhs Another linear congruential random number generator obj.
-       *
-       * @returns true if the two objects are equal, false otherwise.
-       */
-      friend bool
-      operator==(const linear_congruential& __lhs,
-		 const linear_congruential& __rhs)
-      { return __lhs._M_x == __rhs._M_x; }
-
-      /**
-       * Compares two linear congruential random number generator
-       * objects of the same type for inequality.
-       *
-       * @param __lhs A linear congruential random number generator object.
-       * @param __rhs Another linear congruential random number generator obj.
-       *
-       * @returns true if the two objects are not equal, false otherwise.
-       */
-      friend bool
-      operator!=(const linear_congruential& __lhs,
-		 const linear_congruential& __rhs)
-      { return !(__lhs == __rhs); }
-
-      /**
-       * Writes the textual representation of the state x(i) of x to @p __os.
-       *
-       * @param __os  The output stream.
-       * @param __lcr A % linear_congruential random number generator.
-       * @returns __os.
-       */
-      template<class _UIntType1, _UIntType1 __a1, _UIntType1 __c1,
-	       _UIntType1 __m1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const linear_congruential<_UIntType1, __a1, __c1,
-		   __m1>& __lcr);
-
-      /**
-       * Sets the state of the engine by reading its textual
-       * representation from @p __is.
-       *
-       * The textual representation must have been previously written using an
-       * output stream whose imbued locale and whose type's template
-       * specialization arguments _CharT and _Traits were the same as those of
-       * @p __is.
-       *
-       * @param __is  The input stream.
-       * @param __lcr A % linear_congruential random number generator.
-       * @returns __is.
-       */
-      template<class _UIntType1, _UIntType1 __a1, _UIntType1 __c1,
-	       _UIntType1 __m1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   linear_congruential<_UIntType1, __a1, __c1, __m1>& __lcr);
-
-    private:
-      template<class _Gen>
-        void
-        seed(_Gen& __g, true_type)
-        { return seed(static_cast<unsigned long>(__g)); }
-
-      template<class _Gen>
-        void
-        seed(_Gen& __g, false_type);
-
-      _UIntType _M_x;
-    };
-
-  /**
-   * The classic Minimum Standard rand0 of Lewis, Goodman, and Miller.
-   */
-  typedef linear_congruential<unsigned long, 16807, 0, 2147483647> minstd_rand0;
-
-  /**
-   * An alternative LCR (Lehmer Generator function) .
-   */
-  typedef linear_congruential<unsigned long, 48271, 0, 2147483647> minstd_rand;
-
-
-  /**
-   * A generalized feedback shift register discrete random number generator.
-   *
-   * This algorithm avoind multiplication and division and is designed to be
-   * friendly to a pipelined architecture.  If the parameters are chosen
-   * correctly, this generator will produce numbers with a very long period and
-   * fairly good apparent entropy, although still not cryptographically strong.
-   *
-   * The best way to use this generator is with the predefined mt19937 class.
-   *
-   * This algorithm was originally invented by Makoto Matsumoto and
-   * Takuji Nishimura.
-   *
-   * @var word_size   The number of bits in each element of the state vector.
-   * @var state_size  The degree of recursion.
-   * @var shift_size  The period parameter.
-   * @var mask_bits   The separation point bit index.
-   * @var parameter_a The last row of the twist matrix.
-   * @var output_u    The first right-shift tempering matrix parameter.
-   * @var output_s    The first left-shift tempering matrix parameter.
-   * @var output_b    The first left-shift tempering matrix mask.
-   * @var output_t    The second left-shift tempering matrix parameter.
-   * @var output_c    The second left-shift tempering matrix mask.
-   * @var output_l    The second right-shift tempering matrix parameter.
-   */
-  template<class _UIntType, int __w, int __n, int __m, int __r,
-	   _UIntType __a, int __u, int __s, _UIntType __b, int __t,
-	   _UIntType __c, int __l>
-    class mersenne_twister
-    {
-      __glibcxx_class_requires(_UIntType, _UnsignedIntegerConcept)
-
-    public:
-      // types
-      typedef _UIntType result_type;
-
-      // parameter values
-      static const int       word_size   = __w;
-      static const int       state_size  = __n;
-      static const int       shift_size  = __m;
-      static const int       mask_bits   = __r;
-      static const _UIntType parameter_a = __a;
-      static const int       output_u    = __u;
-      static const int       output_s    = __s;
-      static const _UIntType output_b    = __b;
-      static const int       output_t    = __t;
-      static const _UIntType output_c    = __c;
-      static const int       output_l    = __l;
-
-      // constructors and member function
-      mersenne_twister()
-      { seed(); }
-
-      explicit
-      mersenne_twister(unsigned long __value)
-      { seed(__value); }
-
-      template<class _Gen>
-        mersenne_twister(_Gen& __g)
-        { seed(__g); }
-
-      void
-      seed()
-      { seed(5489UL); }
-
-      void
-      seed(unsigned long __value);
-
-      template<class _Gen>
-        void
-        seed(_Gen& __g)
-        { seed(__g, typename is_fundamental<_Gen>::type()); }
-
-      result_type
-      min() const
-      { return 0; };
-
-      result_type
-      max() const
-      { return __detail::_Shift<_UIntType, __w>::__value - 1; }
-
-      result_type
-      operator()();
-
-      /**
-       * Compares two % mersenne_twister random number generator objects of
-       * the same type for equality.
-       *
-       * @param __lhs A % mersenne_twister random number generator object.
-       * @param __rhs Another % mersenne_twister random number generator
-       *              object.
-       *
-       * @returns true if the two objects are equal, false otherwise.
-       */
-      friend bool
-      operator==(const mersenne_twister& __lhs,
-		 const mersenne_twister& __rhs)
-      { return std::equal(__lhs._M_x, __lhs._M_x + state_size, __rhs._M_x); }
-
-      /**
-       * Compares two % mersenne_twister random number generator objects of
-       * the same type for inequality.
-       *
-       * @param __lhs A % mersenne_twister random number generator object.
-       * @param __rhs Another % mersenne_twister random number generator
-       *              object.
-       *
-       * @returns true if the two objects are not equal, false otherwise.
-       */
-      friend bool
-      operator!=(const mersenne_twister& __lhs,
-		 const mersenne_twister& __rhs)
-      { return !(__lhs == __rhs); }
-
-      /**
-       * Inserts the current state of a % mersenne_twister random number
-       * generator engine @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A % mersenne_twister random number generator engine.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<class _UIntType1, int __w1, int __n1, int __m1, int __r1,
-	       _UIntType1 __a1, int __u1, int __s1, _UIntType1 __b1, int __t1,
-	       _UIntType1 __c1, int __l1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const mersenne_twister<_UIntType1, __w1, __n1, __m1, __r1,
-		   __a1, __u1, __s1, __b1, __t1, __c1, __l1>& __x);
-
-      /**
-       * Extracts the current state of a % mersenne_twister random number
-       * generator engine @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A % mersenne_twister random number generator engine.
-       *
-       * @returns The input stream with the state of @p __x extracted or in
-       * an error state.
-       */
-      template<class _UIntType1, int __w1, int __n1, int __m1, int __r1,
-	       _UIntType1 __a1, int __u1, int __s1, _UIntType1 __b1, int __t1,
-	       _UIntType1 __c1, int __l1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   mersenne_twister<_UIntType1, __w1, __n1, __m1, __r1,
-		   __a1, __u1, __s1, __b1, __t1, __c1, __l1>& __x);
-
-    private:
-      template<class _Gen>
-        void
-        seed(_Gen& __g, true_type)
-        { return seed(static_cast<unsigned long>(__g)); }
-
-      template<class _Gen>
-        void
-        seed(_Gen& __g, false_type);
-
-      _UIntType _M_x[state_size];
-      int       _M_p;
-    };
-
-  /**
-   * The classic Mersenne Twister.
-   *
-   * Reference:
-   * M. Matsumoto and T. Nishimura, "Mersenne Twister: A 623-Dimensionally
-   * Equidistributed Uniform Pseudo-Random Number Generator", ACM Transactions
-   * on Modeling and Computer Simulation, Vol. 8, No. 1, January 1998, pp 3-30.
-   */
-  typedef mersenne_twister<
-    unsigned long, 32, 624, 397, 31,
-    0x9908b0dful, 11, 7,
-    0x9d2c5680ul, 15,
-    0xefc60000ul, 18
-    > mt19937;
-
-
-  /**
-   * @brief The Marsaglia-Zaman generator.
-   * 
-   * This is a model of a Generalized Fibonacci discrete random number
-   * generator, sometimes referred to as the SWC generator.
-   *
-   * A discrete random number generator that produces pseudorandom
-   * numbers using @f$x_{i}\leftarrow(x_{i - s} - x_{i - r} -
-   * carry_{i-1}) \bmod m @f$.
-   *
-   * The size of the state is @f$ r @f$
-   * and the maximum period of the generator is @f$ m^r - m^s -1 @f$.
-   *
-   * N1688[4.13] says "the template parameter _IntType shall denote an integral
-   * type large enough to store values up to m."
-   *
-   * @if maint
-   * @var _M_x     The state of the generator.  This is a ring buffer.
-   * @var _M_carry The carry.
-   * @var _M_p     Current index of x(i - r).
-   * @endif
-   */
-  template<typename _IntType, _IntType __m, int __s, int __r>
-    class subtract_with_carry
-    {
-      __glibcxx_class_requires(_IntType, _IntegerConcept)
-
-    public:
-      /** The type of the generated random value. */
-      typedef _IntType result_type;
-      
-      // parameter values
-      static const _IntType modulus   = __m;
-      static const int      long_lag  = __r;
-      static const int      short_lag = __s;
-
-      /**
-       * Constructs a default-initialized % subtract_with_carry random number
-       * generator.
-       */
-      subtract_with_carry()
-      { this->seed(); }
-
-      /**
-       * Constructs an explicitly seeded % subtract_with_carry random number
-       * generator.
-       */
-      explicit
-      subtract_with_carry(unsigned long __value)
-      { this->seed(__value); }
-
-      /**
-       * Constructs a %subtract_with_carry random number generator engine
-       * seeded from the generator function @p __g.
-       *
-       * @param __g The seed generator function.
-       */
-      template<class _Gen>
-        subtract_with_carry(_Gen& __g)
-        { this->seed(__g); }
-
-      /**
-       * Seeds the initial state @f$ x_0 @f$ of the random number generator.
-       *
-       * N1688[4.19] modifies this as follows.  If @p __value == 0,
-       * sets value to 19780503.  In any case, with a linear
-       * congruential generator lcg(i) having parameters @f$ m_{lcg} =
-       * 2147483563, a_{lcg} = 40014, c_{lcg} = 0, and lcg(0) = value
-       * @f$, sets @f$ x_{-r} \dots x_{-1} @f$ to @f$ lcg(1) \bmod m
-       * \dots lcg(r) \bmod m @f$ respectively.  If @f$ x_{-1} = 0 @f$
-       * set carry to 1, otherwise sets carry to 0.
-       */
-      void
-      seed(unsigned long __value = 19780503);
-
-      /**
-       * Seeds the initial state @f$ x_0 @f$ of the % subtract_with_carry
-       * random number generator.
-       */
-      template<class _Gen>
-        void
-        seed(_Gen& __g)
-        { seed(__g, typename is_fundamental<_Gen>::type()); }
-
-      /**
-       * Gets the inclusive minimum value of the range of random integers
-       * returned by this generator.
-       */
-      result_type
-      min() const
-      { return 0; }
-
-      /**
-       * Gets the inclusive maximum value of the range of random integers
-       * returned by this generator.
-       */
-      result_type
-      max() const
-      { return this->modulus - 1; }
-
-      /**
-       * Gets the next random number in the sequence.
-       */
-      result_type
-      operator()();
-
-      /**
-       * Compares two % subtract_with_carry random number generator objects of
-       * the same type for equality.
-       *
-       * @param __lhs A % subtract_with_carry random number generator object.
-       * @param __rhs Another % subtract_with_carry random number generator
-       *              object.
-       *
-       * @returns true if the two objects are equal, false otherwise.
-       */
-      friend bool
-      operator==(const subtract_with_carry& __lhs,
-		 const subtract_with_carry& __rhs)
-      { return std::equal(__lhs._M_x, __lhs._M_x + long_lag, __rhs._M_x); }
-
-      /**
-       * Compares two % subtract_with_carry random number generator objects of
-       * the same type for inequality.
-       *
-       * @param __lhs A % subtract_with_carry random number generator object.
-       * @param __rhs Another % subtract_with_carry random number generator
-       *              object.
-       *
-       * @returns true if the two objects are not equal, false otherwise.
-       */
-      friend bool
-      operator!=(const subtract_with_carry& __lhs,
-		 const subtract_with_carry& __rhs)
-      { return !(__lhs == __rhs); }
-
-      /**
-       * Inserts the current state of a % subtract_with_carry random number
-       * generator engine @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A % subtract_with_carry random number generator engine.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _IntType1, _IntType1 __m1, int __s1, int __r1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const subtract_with_carry<_IntType1, __m1, __s1,
-		   __r1>& __x);
-
-      /**
-       * Extracts the current state of a % subtract_with_carry random number
-       * generator engine @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A % subtract_with_carry random number generator engine.
-       *
-       * @returns The input stream with the state of @p __x extracted or in
-       * an error state.
-       */
-      template<typename _IntType1, _IntType1 __m1, int __s1, int __r1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   subtract_with_carry<_IntType1, __m1, __s1, __r1>& __x);
-
-    private:
-      template<class _Gen>
-        void
-        seed(_Gen& __g, true_type)
-        { return seed(static_cast<unsigned long>(__g)); }
-
-      template<class _Gen>
-        void
-        seed(_Gen& __g, false_type);
-
-      typedef typename __gnu_cxx::__add_unsigned<_IntType>::__type _UIntType;
-
-      _UIntType  _M_x[long_lag];
-      _UIntType  _M_carry;
-      int        _M_p;
-    };
-
-
-  /**
-   * @brief The Marsaglia-Zaman generator (floats version).
-   *
-   * @if maint
-   * @var _M_x     The state of the generator.  This is a ring buffer.
-   * @var _M_carry The carry.
-   * @var _M_p     Current index of x(i - r).
-   * @var _M_npows Precomputed negative powers of 2.   
-   * @endif
-   */
-  template<typename _RealType, int __w, int __s, int __r>
-    class subtract_with_carry_01
-    {
-    public:
-      /** The type of the generated random value. */
-      typedef _RealType result_type;
-      
-      // parameter values
-      static const int      word_size = __w;
-      static const int      long_lag  = __r;
-      static const int      short_lag = __s;
-
-      /**
-       * Constructs a default-initialized % subtract_with_carry_01 random
-       * number generator.
-       */
-      subtract_with_carry_01()
-      {
-	this->seed();
-	_M_initialize_npows();
-      }
-
-      /**
-       * Constructs an explicitly seeded % subtract_with_carry_01 random number
-       * generator.
-       */
-      explicit
-      subtract_with_carry_01(unsigned long __value)
-      {
-	this->seed(__value);
-	_M_initialize_npows();
-      }
-
-      /**
-       * Constructs a % subtract_with_carry_01 random number generator engine
-       * seeded from the generator function @p __g.
-       *
-       * @param __g The seed generator function.
-       */
-      template<class _Gen>
-        subtract_with_carry_01(_Gen& __g)
-        {
-	  this->seed(__g);
-	  _M_initialize_npows();	  
-	}
-
-      /**
-       * Seeds the initial state @f$ x_0 @f$ of the random number generator.
-       */
-      void
-      seed(unsigned long __value = 19780503);
-
-      /**
-       * Seeds the initial state @f$ x_0 @f$ of the % subtract_with_carry_01
-       * random number generator.
-       */
-      template<class _Gen>
-        void
-        seed(_Gen& __g)
-        { seed(__g, typename is_fundamental<_Gen>::type()); }
-
-      /**
-       * Gets the minimum value of the range of random floats
-       * returned by this generator.
-       */
-      result_type
-      min() const
-      { return 0.0; }
-
-      /**
-       * Gets the maximum value of the range of random floats
-       * returned by this generator.
-       */
-      result_type
-      max() const
-      { return 1.0; }
-
-      /**
-       * Gets the next random number in the sequence.
-       */
-      result_type
-      operator()();
-
-      /**
-       * Compares two % subtract_with_carry_01 random number generator objects
-       * of the same type for equality.
-       *
-       * @param __lhs A % subtract_with_carry_01 random number
-       *              generator object.
-       * @param __rhs Another % subtract_with_carry_01 random number generator
-       *              object.
-       *
-       * @returns true if the two objects are equal, false otherwise.
-       */
-      friend bool
-      operator==(const subtract_with_carry_01& __lhs,
-		 const subtract_with_carry_01& __rhs)
-      {
-	for (int __i = 0; __i < long_lag; ++__i)
-	  if (!std::equal(__lhs._M_x[__i], __lhs._M_x[__i] + __n,
-			  __rhs._M_x[__i]))
-	    return false;
-	return true;
-      }
-
-      /**
-       * Compares two % subtract_with_carry_01 random number generator objects
-       * of the same type for inequality.
-       *
-       * @param __lhs A % subtract_with_carry_01 random number
-       *              generator object.
-       *
-       * @param __rhs Another % subtract_with_carry_01 random number generator
-       *              object.
-       *
-       * @returns true if the two objects are not equal, false otherwise.
-       */
-      friend bool
-      operator!=(const subtract_with_carry_01& __lhs,
-		 const subtract_with_carry_01& __rhs)
-      { return !(__lhs == __rhs); }
-
-      /**
-       * Inserts the current state of a % subtract_with_carry_01 random number
-       * generator engine @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A % subtract_with_carry_01 random number generator engine.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _RealType1, int __w1, int __s1, int __r1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const subtract_with_carry_01<_RealType1, __w1, __s1,
-		   __r1>& __x);
-
-      /**
-       * Extracts the current state of a % subtract_with_carry_01 random number
-       * generator engine @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A % subtract_with_carry_01 random number generator engine.
-       *
-       * @returns The input stream with the state of @p __x extracted or in
-       * an error state.
-       */
-      template<typename _RealType1, int __w1, int __s1, int __r1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   subtract_with_carry_01<_RealType1, __w1, __s1, __r1>& __x);
-
-    private:
-      template<class _Gen>
-        void
-        seed(_Gen& __g, true_type)
-        { return seed(static_cast<unsigned long>(__g)); }
-
-      template<class _Gen>
-        void
-        seed(_Gen& __g, false_type);
-
-      void
-      _M_initialize_npows();
-
-      static const int __n = (__w + 31) / 32;
-
-      typedef __detail::_UInt32Type _UInt32Type;
-      _UInt32Type  _M_x[long_lag][__n];
-      _RealType    _M_npows[__n];
-      _UInt32Type  _M_carry;
-      int          _M_p;
-    };
-
-  typedef subtract_with_carry_01<float, 24, 10, 24>   ranlux_base_01;
-
-  // _GLIBCXX_RESOLVE_LIB_DEFECTS
-  // 508. Bad parameters for ranlux64_base_01.
-  typedef subtract_with_carry_01<double, 48, 5, 12> ranlux64_base_01;  
-
-
-  /**
-   * Produces random numbers from some base engine by discarding blocks of
-   * data.
-   *
-   * 0 <= @p __r <= @p __p
-   */
-  template<class _UniformRandomNumberGenerator, int __p, int __r>
-    class discard_block
-    {
-      // __glibcxx_class_requires(typename base_type::result_type,
-      //                          ArithmeticTypeConcept)
-
-    public:
-      /** The type of the underlying generator engine. */
-      typedef _UniformRandomNumberGenerator   base_type;
-      /** The type of the generated random value. */
-      typedef typename base_type::result_type result_type;
-
-      // parameter values
-      static const int block_size = __p;
-      static const int used_block = __r;
-
-      /**
-       * Constructs a default %discard_block engine.
-       *
-       * The underlying engine is default constructed as well.
-       */
-      discard_block()
-      : _M_n(0) { }
-
-      /**
-       * Copy constructs a %discard_block engine.
-       *
-       * Copies an existing base class random number geenerator.
-       * @param rng An existing (base class) engine object.
-       */
-      explicit
-      discard_block(const base_type& __rng)
-      : _M_b(__rng), _M_n(0) { }
-
-      /**
-       * Seed constructs a %discard_block engine.
-       *
-       * Constructs the underlying generator engine seeded with @p __s.
-       * @param __s A seed value for the base class engine.
-       */
-      explicit
-      discard_block(unsigned long __s)
-      : _M_b(__s), _M_n(0) { }
-
-      /**
-       * Generator construct a %discard_block engine.
-       *
-       * @param __g A seed generator function.
-       */
-      template<class _Gen>
-        discard_block(_Gen& __g)
-	: _M_b(__g), _M_n(0) { }
-
-      /**
-       * Reseeds the %discard_block object with the default seed for the
-       * underlying base class generator engine.
-       */
-      void seed()
-      {
-	_M_b.seed();
-	_M_n = 0;
-      }
-
-      /**
-       * Reseeds the %discard_block object with the given seed generator
-       * function.
-       * @param __g A seed generator function.
-       */
-      template<class _Gen>
-        void seed(_Gen& __g)
-        {
-	  _M_b.seed(__g);
-	  _M_n = 0;
-	}
-
-      /**
-       * Gets a const reference to the underlying generator engine object.
-       */
-      const base_type&
-      base() const
-      { return _M_b; }
-
-      /**
-       * Gets the minimum value in the generated random number range.
-       */
-      result_type
-      min() const
-      { return _M_b.min(); }
-
-      /**
-       * Gets the maximum value in the generated random number range.
-       */
-      result_type
-      max() const
-      { return _M_b.max(); }
-
-      /**
-       * Gets the next value in the generated random number sequence.
-       */
-      result_type
-      operator()();
-
-      /**
-       * Compares two %discard_block random number generator objects of
-       * the same type for equality.
-       *
-       * @param __lhs A %discard_block random number generator object.
-       * @param __rhs Another %discard_block random number generator
-       *              object.
-       *
-       * @returns true if the two objects are equal, false otherwise.
-       */
-      friend bool
-      operator==(const discard_block& __lhs, const discard_block& __rhs)
-      { return (__lhs._M_b == __rhs._M_b) && (__lhs._M_n == __rhs._M_n); }
-
-      /**
-       * Compares two %discard_block random number generator objects of
-       * the same type for inequality.
-       *
-       * @param __lhs A %discard_block random number generator object.
-       * @param __rhs Another %discard_block random number generator
-       *              object.
-       *
-       * @returns true if the two objects are not equal, false otherwise.
-       */
-      friend bool
-      operator!=(const discard_block& __lhs, const discard_block& __rhs)
-      { return !(__lhs == __rhs); }
-
-      /**
-       * Inserts the current state of a %discard_block random number
-       * generator engine @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %discard_block random number generator engine.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<class _UniformRandomNumberGenerator1, int __p1, int __r1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const discard_block<_UniformRandomNumberGenerator1,
-		   __p1, __r1>& __x);
-
-      /**
-       * Extracts the current state of a % subtract_with_carry random number
-       * generator engine @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A %discard_block random number generator engine.
-       *
-       * @returns The input stream with the state of @p __x extracted or in
-       * an error state.
-       */
-      template<class _UniformRandomNumberGenerator1, int __p1, int __r1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   discard_block<_UniformRandomNumberGenerator1,
-		   __p1, __r1>& __x);
-
-    private:
-      base_type _M_b;
-      int       _M_n;
-    };
-
-
-  /**
-   * James's luxury-level-3 integer adaptation of Luescher's generator.
-   */
-  typedef discard_block<
-    subtract_with_carry<unsigned long, (1UL << 24), 10, 24>,
-      223,
-      24
-      > ranlux3;
-
-  /**
-   * James's luxury-level-4 integer adaptation of Luescher's generator.
-   */
-  typedef discard_block<
-    subtract_with_carry<unsigned long, (1UL << 24), 10, 24>,
-      389,
-      24
-      > ranlux4;
-
-  typedef discard_block<
-    subtract_with_carry_01<float, 24, 10, 24>,
-      223,
-      24
-      > ranlux3_01;
-
-  typedef discard_block<
-    subtract_with_carry_01<float, 24, 10, 24>,
-      389,
-      24
-      > ranlux4_01;
-
-
-  /**
-   * A random number generator adaptor class that combines two random number
-   * generator engines into a single output sequence.
-   */
-  template<class _UniformRandomNumberGenerator1, int __s1,
-	   class _UniformRandomNumberGenerator2, int __s2>
-    class xor_combine
-    {
-      // __glibcxx_class_requires(typename _UniformRandomNumberGenerator1::
-      //                          result_type, ArithmeticTypeConcept)
-      // __glibcxx_class_requires(typename _UniformRandomNumberGenerator2::
-      //                          result_type, ArithmeticTypeConcept)
-
-    public:
-      /** The type of the the first underlying generator engine. */
-      typedef _UniformRandomNumberGenerator1   base1_type;
-      /** The type of the the second underlying generator engine. */
-      typedef _UniformRandomNumberGenerator2   base2_type;
-
-    private:
-      typedef typename base1_type::result_type _Result_type1;
-      typedef typename base2_type::result_type _Result_type2;
-
-    public:
-      /** The type of the generated random value. */
-      typedef typename __gnu_cxx::__conditional_type<(sizeof(_Result_type1)
-						      > sizeof(_Result_type2)),
-	_Result_type1, _Result_type2>::__type result_type;
-
-      // parameter values
-      static const int shift1 = __s1;
-      static const int shift2 = __s2;
-
-      // constructors and member function
-      xor_combine()
-      : _M_b1(), _M_b2()	
-      { _M_initialize_max(); }
-
-      xor_combine(const base1_type& __rng1, const base2_type& __rng2)
-      : _M_b1(__rng1), _M_b2(__rng2)
-      { _M_initialize_max(); }
-
-      xor_combine(unsigned long __s)
-      : _M_b1(__s), _M_b2(__s + 1)
-      { _M_initialize_max(); }
-
-      template<class _Gen>
-        xor_combine(_Gen& __g)
-	: _M_b1(__g), _M_b2(__g)
-        { _M_initialize_max(); }
-
-      void
-      seed()
-      {
-	_M_b1.seed();
-	_M_b2.seed();
-      }
-
-      template<class _Gen>
-        void
-        seed(_Gen& __g)
-        {
-	  _M_b1.seed(__g);
-	  _M_b2.seed(__g);
-	}
-
-      const base1_type&
-      base1() const
-      { return _M_b1; }
-
-      const base2_type&
-      base2() const
-      { return _M_b2; }
-
-      result_type
-      min() const
-      { return 0; }
-
-      result_type
-      max() const
-      { return _M_max; }
-
-      /**
-       * Gets the next random number in the sequence.
-       */
-      // NB: Not exactly the TR1 formula, per N2079 instead.
-      result_type
-      operator()()
-      {
-	return ((result_type(_M_b1() - _M_b1.min()) << shift1)
-		^ (result_type(_M_b2() - _M_b2.min()) << shift2));
-      }
-
-      /**
-       * Compares two %xor_combine random number generator objects of
-       * the same type for equality.
-       *
-       * @param __lhs A %xor_combine random number generator object.
-       * @param __rhs Another %xor_combine random number generator
-       *              object.
-       *
-       * @returns true if the two objects are equal, false otherwise.
-       */
-      friend bool
-      operator==(const xor_combine& __lhs, const xor_combine& __rhs)
-      {
-	return (__lhs.base1() == __rhs.base1())
-	        && (__lhs.base2() == __rhs.base2());
-      }
-
-      /**
-       * Compares two %xor_combine random number generator objects of
-       * the same type for inequality.
-       *
-       * @param __lhs A %xor_combine random number generator object.
-       * @param __rhs Another %xor_combine random number generator
-       *              object.
-       *
-       * @returns true if the two objects are not equal, false otherwise.
-       */
-      friend bool
-      operator!=(const xor_combine& __lhs, const xor_combine& __rhs)
-      { return !(__lhs == __rhs); }
-
-      /**
-       * Inserts the current state of a %xor_combine random number
-       * generator engine @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %xor_combine random number generator engine.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<class _UniformRandomNumberGenerator11, int __s11,
-	       class _UniformRandomNumberGenerator21, int __s21,
-	       typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const xor_combine<_UniformRandomNumberGenerator11, __s11,
-		   _UniformRandomNumberGenerator21, __s21>& __x);
-
-      /**
-       * Extracts the current state of a %xor_combine random number
-       * generator engine @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A %xor_combine random number generator engine.
-       *
-       * @returns The input stream with the state of @p __x extracted or in
-       * an error state.
-       */
-      template<class _UniformRandomNumberGenerator11, int __s11,
-	       class _UniformRandomNumberGenerator21, int __s21,
-	       typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   xor_combine<_UniformRandomNumberGenerator11, __s11,
-		   _UniformRandomNumberGenerator21, __s21>& __x);
-
-    private:
-      void
-      _M_initialize_max();
-
-      result_type
-      _M_initialize_max_aux(result_type, result_type, int);
-
-      base1_type  _M_b1;
-      base2_type  _M_b2;
-      result_type _M_max;
-    };
-
-
-  /**
-   * A standard interface to a platform-specific non-deterministic
-   * random number generator (if any are available).
-   */
-  class random_device
-  {
-  public:
-    // types
-    typedef unsigned int result_type;
-
-    // constructors, destructors and member functions
-
-#ifdef _GLIBCXX_USE_RANDOM_TR1
-
-    explicit
-    random_device(const std::string& __token = "/dev/urandom")
-    {
-      if ((__token != "/dev/urandom" && __token != "/dev/random")
-	  || !(_M_file = std::fopen(__token.c_str(), "rb")))
-	std::__throw_runtime_error(__N("random_device::"
-				       "random_device(const std::string&)"));
-    }
-
-    ~random_device()
-    { std::fclose(_M_file); }
-
-#else
-
-    explicit
-    random_device(const std::string& __token = "mt19937")
-    : _M_mt(_M_strtoul(__token)) { }
-
-  private:
-    static unsigned long
-    _M_strtoul(const std::string& __str)
-    {
-      unsigned long __ret = 5489UL;
-      if (__str != "mt19937")
-	{
-	  const char* __nptr = __str.c_str();
-	  char* __endptr;
-	  __ret = std::strtoul(__nptr, &__endptr, 0);
-	  if (*__nptr == '\0' || *__endptr != '\0')
-	    std::__throw_runtime_error(__N("random_device::_M_strtoul"
-					   "(const std::string&)"));
-	}
-      return __ret;
-    }
-
-  public:
-
-#endif
-
-    result_type
-    min() const
-    { return std::numeric_limits<result_type>::min(); }
-
-    result_type
-    max() const
-    { return std::numeric_limits<result_type>::max(); }
-
-    double
-    entropy() const
-    { return 0.0; }
-
-    result_type
-    operator()()
-    {
-#ifdef _GLIBCXX_USE_RANDOM_TR1
-      result_type __ret;
-      std::fread(reinterpret_cast<void*>(&__ret), sizeof(result_type),
-		 1, _M_file);
-      return __ret;
-#else
-      return _M_mt();
-#endif
-    }
-
-  private:
-    random_device(const random_device&);
-    void operator=(const random_device&);
-
-#ifdef _GLIBCXX_USE_RANDOM_TR1
-    FILE*        _M_file;
+#if defined(_GLIBCXX_INCLUDE_AS_TR1)
+#  include <tr1_impl/random>
 #else
-    mt19937      _M_mt;
+#  define _GLIBCXX_INCLUDE_AS_TR1
+#  define _GLIBCXX_BEGIN_NAMESPACE_TR1 namespace tr1 {
+#  define _GLIBCXX_END_NAMESPACE_TR1 }
+#  define _GLIBCXX_TR1 tr1::
+#  include <tr1_impl/random>
+#  undef _GLIBCXX_TR1
+#  undef _GLIBCXX_END_NAMESPACE_TR1
+#  undef _GLIBCXX_BEGIN_NAMESPACE_TR1
+#  undef _GLIBCXX_INCLUDE_AS_TR1
 #endif
-  };
-
-  /* @} */ // group tr1_random_generators
-
-  /**
-   * @addtogroup tr1_random_distributions Random Number Distributions
-   * @ingroup tr1_random
-   * @{
-   */
-
-  /**
-   * @addtogroup tr1_random_distributions_discrete Discrete Distributions
-   * @ingroup tr1_random_distributions
-   * @{
-   */
-
-  /**
-   * @brief Uniform discrete distribution for random numbers.
-   * A discrete random distribution on the range @f$[min, max]@f$ with equal
-   * probability throughout the range.
-   */
-  template<typename _IntType = int>
-    class uniform_int
-    {
-      __glibcxx_class_requires(_IntType, _IntegerConcept)
- 
-    public:
-      /** The type of the parameters of the distribution. */
-      typedef _IntType input_type;
-      /** The type of the range of the distribution. */
-      typedef _IntType result_type;
-
-    public:
-      /**
-       * Constructs a uniform distribution object.
-       */
-      explicit
-      uniform_int(_IntType __min = 0, _IntType __max = 9)
-      : _M_min(__min), _M_max(__max)
-      {
-	_GLIBCXX_DEBUG_ASSERT(_M_min <= _M_max);
-      }
-
-      /**
-       * Gets the inclusive lower bound of the distribution range.
-       */
-      result_type
-      min() const
-      { return _M_min; }
-
-      /**
-       * Gets the inclusive upper bound of the distribution range.
-       */
-      result_type
-      max() const
-      { return _M_max; }
-
-      /**
-       * Resets the distribution state.
-       *
-       * Does nothing for the uniform integer distribution.
-       */
-      void
-      reset() { }
-
-      /**
-       * Gets a uniformly distributed random number in the range
-       * @f$(min, max)@f$.
-       */
-      template<typename _UniformRandomNumberGenerator>
-        result_type
-        operator()(_UniformRandomNumberGenerator& __urng)
-        {
-	  typedef typename _UniformRandomNumberGenerator::result_type
-	    _UResult_type;
-	  return _M_call(__urng, _M_min, _M_max,
-			 typename is_integral<_UResult_type>::type());
-	}
-
-      /**
-       * Gets a uniform random number in the range @f$[0, n)@f$.
-       *
-       * This function is aimed at use with std::random_shuffle.
-       */
-      template<typename _UniformRandomNumberGenerator>
-        result_type
-        operator()(_UniformRandomNumberGenerator& __urng, result_type __n)
-        {
-	  typedef typename _UniformRandomNumberGenerator::result_type
-	    _UResult_type;
-	  return _M_call(__urng, 0, __n - 1,
-			 typename is_integral<_UResult_type>::type());
-	}
-
-      /**
-       * Inserts a %uniform_int random number distribution @p __x into the
-       * output stream @p os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %uniform_int random number distribution.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _IntType1, typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const uniform_int<_IntType1>& __x);
-
-      /**
-       * Extracts a %unform_int random number distribution
-       * @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A %uniform_int random number generator engine.
-       *
-       * @returns The input stream with @p __x extracted or in an error state.
-       */
-      template<typename _IntType1, typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   uniform_int<_IntType1>& __x);
-
-    private:
-      template<typename _UniformRandomNumberGenerator>
-        result_type
-        _M_call(_UniformRandomNumberGenerator& __urng,
-		result_type __min, result_type __max, true_type)
-        { return result_type(__urng() % (__max - __min + 1)) + __min; }
-
-      template<typename _UniformRandomNumberGenerator>
-        result_type
-        _M_call(_UniformRandomNumberGenerator& __urng,
-		result_type __min, result_type __max, false_type)
-        {
-	  return result_type((__urng() - __urng.min())
-			     / (__urng.max() - __urng.min())
-			     * (__max - __min + 1)) + __min;
-	}
-
-      _IntType _M_min;
-      _IntType _M_max;
-    };
-
-
-  /**
-   * @brief A Bernoulli random number distribution.
-   *
-   * Generates a sequence of true and false values with likelihood @f$ p @f$
-   * that true will come up and @f$ (1 - p) @f$ that false will appear.
-   */
-  class bernoulli_distribution
-  {
-  public:
-    typedef int  input_type;
-    typedef bool result_type;
-
-  public:
-    /**
-     * Constructs a Bernoulli distribution with likelihood @p p.
-     *
-     * @param __p  [IN]  The likelihood of a true result being returned.  Must
-     * be in the interval @f$ [0, 1] @f$.
-     */
-    explicit
-    bernoulli_distribution(double __p = 0.5)
-    : _M_p(__p)
-    { 
-      _GLIBCXX_DEBUG_ASSERT((_M_p >= 0.0) && (_M_p <= 1.0));
-    }
-
-    /**
-     * Gets the @p p parameter of the distribution.
-     */
-    double
-    p() const
-    { return _M_p; }
-
-    /**
-     * Resets the distribution state.
-     *
-     * Does nothing for a bernoulli distribution.
-     */
-    void
-    reset() { }
-
-    /**
-     * Gets the next value in the Bernoullian sequence.
-     */
-    template<class _UniformRandomNumberGenerator>
-      result_type
-      operator()(_UniformRandomNumberGenerator& __urng)
-      {
-	if ((__urng() - __urng.min()) < _M_p * (__urng.max() - __urng.min()))
-	  return true;
-	return false;
-      }
-
-    /**
-     * Inserts a %bernoulli_distribution random number distribution
-     * @p __x into the output stream @p __os.
-     *
-     * @param __os An output stream.
-     * @param __x  A %bernoulli_distribution random number distribution.
-     *
-     * @returns The output stream with the state of @p __x inserted or in
-     * an error state.
-     */
-    template<typename _CharT, typename _Traits>
-      friend std::basic_ostream<_CharT, _Traits>&
-      operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		 const bernoulli_distribution& __x);
-
-    /**
-     * Extracts a %bernoulli_distribution random number distribution
-     * @p __x from the input stream @p __is.
-     *
-     * @param __is An input stream.
-     * @param __x  A %bernoulli_distribution random number generator engine.
-     *
-     * @returns The input stream with @p __x extracted or in an error state.
-     */
-    template<typename _CharT, typename _Traits>
-      friend std::basic_istream<_CharT, _Traits>&
-      operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		 bernoulli_distribution& __x)
-      { return __is >> __x._M_p; }
-
-  private:
-    double _M_p;
-  };
-
-
-  /**
-   * @brief A discrete geometric random number distribution.
-   *
-   * The formula for the geometric probability mass function is 
-   * @f$ p(i) = (1 - p)p^{i-1} @f$ where @f$ p @f$ is the parameter of the
-   * distribution.
-   */
-  template<typename _IntType = int, typename _RealType = double>
-    class geometric_distribution
-    {
-    public:
-      // types
-      typedef _RealType input_type;
-      typedef _IntType  result_type;
-
-      // constructors and member function
-      explicit
-      geometric_distribution(const _RealType& __p = _RealType(0.5))
-      : _M_p(__p)
-      {
-	_GLIBCXX_DEBUG_ASSERT((_M_p > 0.0) && (_M_p < 1.0));
-	_M_initialize();
-      }
-
-      /**
-       * Gets the distribution parameter @p p.
-       */
-      _RealType
-      p() const
-      { return _M_p; }
-
-      void
-      reset() { }
-
-      template<class _UniformRandomNumberGenerator>
-        result_type
-        operator()(_UniformRandomNumberGenerator& __urng);
-
-      /**
-       * Inserts a %geometric_distribution random number distribution
-       * @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %geometric_distribution random number distribution.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _IntType1, typename _RealType1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const geometric_distribution<_IntType1, _RealType1>& __x);
-
-      /**
-       * Extracts a %geometric_distribution random number distribution
-       * @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A %geometric_distribution random number generator engine.
-       *
-       * @returns The input stream with @p __x extracted or in an error state.
-       */
-      template<typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   geometric_distribution& __x)
-        {
-	  __is >> __x._M_p;
-	  __x._M_initialize();
-	  return __is;
-	}
-
-    private:
-      void
-      _M_initialize()
-      { _M_log_p = std::log(_M_p); }
-
-      _RealType _M_p;
-      _RealType _M_log_p;
-    };
-
-
-  template<typename _RealType>
-    class normal_distribution;
-
-  /**
-   * @brief A discrete Poisson random number distribution.
-   *
-   * The formula for the poisson probability mass function is 
-   * @f$ p(i) = \frac{mean^i}{i!} e^{-mean} @f$ where @f$ mean @f$ is the
-   * parameter of the distribution.
-   */
-  template<typename _IntType = int, typename _RealType = double>
-    class poisson_distribution
-    {
-    public:
-      // types
-      typedef _RealType input_type;
-      typedef _IntType  result_type;
-
-      // constructors and member function
-      explicit
-      poisson_distribution(const _RealType& __mean = _RealType(1))
-      : _M_mean(__mean), _M_nd()
-      {
-	_GLIBCXX_DEBUG_ASSERT(_M_mean > 0.0);
-	_M_initialize();
-      }
-
-      /**
-       * Gets the distribution parameter @p mean.
-       */
-      _RealType
-      mean() const
-      { return _M_mean; }
-
-      void
-      reset()
-      { _M_nd.reset(); }
-
-      template<class _UniformRandomNumberGenerator>
-        result_type
-        operator()(_UniformRandomNumberGenerator& __urng);
-
-      /**
-       * Inserts a %poisson_distribution random number distribution
-       * @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %poisson_distribution random number distribution.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _IntType1, typename _RealType1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const poisson_distribution<_IntType1, _RealType1>& __x);
-
-      /**
-       * Extracts a %poisson_distribution random number distribution
-       * @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A %poisson_distribution random number generator engine.
-       *
-       * @returns The input stream with @p __x extracted or in an error state.
-       */
-      template<typename _IntType1, typename _RealType1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   poisson_distribution<_IntType1, _RealType1>& __x);
-
-    private:
-      void
-      _M_initialize();
-
-      // NB: Unused when _GLIBCXX_USE_C99_MATH_TR1 is undefined.
-      normal_distribution<_RealType> _M_nd;
-
-      _RealType _M_mean;
-
-      // Hosts either log(mean) or the threshold of the simple method.
-      _RealType _M_lm_thr;
-#if _GLIBCXX_USE_C99_MATH_TR1
-      _RealType _M_lfm, _M_sm, _M_d, _M_scx, _M_1cx, _M_c2b, _M_cb;
-#endif
-    };
-
-
-  /**
-   * @brief A discrete binomial random number distribution.
-   *
-   * The formula for the binomial probability mass function is 
-   * @f$ p(i) = \binom{n}{i} p^i (1 - p)^{t - i} @f$ where @f$ t @f$
-   * and @f$ p @f$ are the parameters of the distribution.
-   */
-  template<typename _IntType = int, typename _RealType = double>
-    class binomial_distribution
-    {
-    public:
-      // types
-      typedef _RealType input_type;
-      typedef _IntType  result_type;
-
-      // constructors and member function
-      explicit
-      binomial_distribution(_IntType __t = 1,
-			    const _RealType& __p = _RealType(0.5))
-      : _M_t(__t), _M_p(__p), _M_nd()
-      {
-	_GLIBCXX_DEBUG_ASSERT((_M_t >= 0) && (_M_p >= 0.0) && (_M_p <= 1.0));
-	_M_initialize();
-      }
-
-      /**
-       * Gets the distribution @p t parameter.
-       */
-      _IntType
-      t() const
-      { return _M_t; }
-      
-      /**
-       * Gets the distribution @p p parameter.
-       */
-      _RealType
-      p() const
-      { return _M_p; }
-
-      void
-      reset()
-      { _M_nd.reset(); }
-
-      template<class _UniformRandomNumberGenerator>
-        result_type
-        operator()(_UniformRandomNumberGenerator& __urng);
-
-      /**
-       * Inserts a %binomial_distribution random number distribution
-       * @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %binomial_distribution random number distribution.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _IntType1, typename _RealType1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const binomial_distribution<_IntType1, _RealType1>& __x);
-
-      /**
-       * Extracts a %binomial_distribution random number distribution
-       * @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A %binomial_distribution random number generator engine.
-       *
-       * @returns The input stream with @p __x extracted or in an error state.
-       */
-      template<typename _IntType1, typename _RealType1,
-	       typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   binomial_distribution<_IntType1, _RealType1>& __x);
-
-    private:
-      void
-      _M_initialize();
-
-      template<class _UniformRandomNumberGenerator>
-        result_type
-        _M_waiting(_UniformRandomNumberGenerator& __urng, _IntType __t);
-
-      // NB: Unused when _GLIBCXX_USE_C99_MATH_TR1 is undefined.
-      normal_distribution<_RealType> _M_nd;
-
-      _RealType _M_q;
-#if _GLIBCXX_USE_C99_MATH_TR1
-      _RealType _M_d1, _M_d2, _M_s1, _M_s2, _M_c,
-	        _M_a1, _M_a123, _M_s, _M_lf, _M_lp1p;
-#endif
-      _RealType _M_p;
-      _IntType  _M_t;
-
-      bool      _M_easy;
-    };
-
-  /* @} */ // group tr1_random_distributions_discrete
-
-  /**
-   * @addtogroup tr1_random_distributions_continuous Continuous Distributions
-   * @ingroup tr1_random_distributions
-   * @{
-   */
-
-  /**
-   * @brief Uniform continuous distribution for random numbers.
-   *
-   * A continuous random distribution on the range [min, max) with equal
-   * probability throughout the range.  The URNG should be real-valued and
-   * deliver number in the range [0, 1).
-   */
-  template<typename _RealType = double>
-    class uniform_real
-    {
-    public:
-      // types
-      typedef _RealType input_type;
-      typedef _RealType result_type;
-
-    public:
-      /**
-       * Constructs a uniform_real object.
-       *
-       * @param __min [IN]  The lower bound of the distribution.
-       * @param __max [IN]  The upper bound of the distribution.
-       */
-      explicit
-      uniform_real(_RealType __min = _RealType(0),
-		   _RealType __max = _RealType(1))
-      : _M_min(__min), _M_max(__max)
-      {
-	_GLIBCXX_DEBUG_ASSERT(_M_min <= _M_max);
-      }
-
-      result_type
-      min() const
-      { return _M_min; }
-
-      result_type
-      max() const
-      { return _M_max; }
-
-      void
-      reset() { }
-
-      template<class _UniformRandomNumberGenerator>
-        result_type
-        operator()(_UniformRandomNumberGenerator& __urng)
-        { return (__urng() * (_M_max - _M_min)) + _M_min; }
-
-      /**
-       * Inserts a %uniform_real random number distribution @p __x into the
-       * output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %uniform_real random number distribution.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _RealType1, typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const uniform_real<_RealType1>& __x);
-
-      /**
-       * Extracts a %unform_real random number distribution
-       * @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A %uniform_real random number generator engine.
-       *
-       * @returns The input stream with @p __x extracted or in an error state.
-       */
-      template<typename _RealType1, typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   uniform_real<_RealType1>& __x);
-
-    private:
-      _RealType _M_min;
-      _RealType _M_max;
-    };
-
-
-  /**
-   * @brief An exponential continuous distribution for random numbers.
-   *
-   * The formula for the exponential probability mass function is 
-   * @f$ p(x) = \lambda e^{-\lambda x} @f$.
-   *
-   * <table border=1 cellpadding=10 cellspacing=0>
-   * <caption align=top>Distribution Statistics</caption>
-   * <tr><td>Mean</td><td>@f$ \frac{1}{\lambda} @f$</td></tr>
-   * <tr><td>Median</td><td>@f$ \frac{\ln 2}{\lambda} @f$</td></tr>
-   * <tr><td>Mode</td><td>@f$ zero @f$</td></tr>
-   * <tr><td>Range</td><td>@f$[0, \infty]@f$</td></tr>
-   * <tr><td>Standard Deviation</td><td>@f$ \frac{1}{\lambda} @f$</td></tr>
-   * </table>
-   */
-  template<typename _RealType = double>
-    class exponential_distribution
-    {
-    public:
-      // types
-      typedef _RealType input_type;
-      typedef _RealType result_type;
-
-    public:
-      /**
-       * Constructs an exponential distribution with inverse scale parameter
-       * @f$ \lambda @f$.
-       */
-      explicit
-      exponential_distribution(const result_type& __lambda = result_type(1))
-      : _M_lambda(__lambda)
-      { 
-	_GLIBCXX_DEBUG_ASSERT(_M_lambda > 0);
-      }
-
-      /**
-       * Gets the inverse scale parameter of the distribution.
-       */
-      _RealType
-      lambda() const
-      { return _M_lambda; }
-
-      /**
-       * Resets the distribution.
-       *
-       * Has no effect on exponential distributions.
-       */
-      void
-      reset() { }
-
-      template<class _UniformRandomNumberGenerator>
-        result_type
-        operator()(_UniformRandomNumberGenerator& __urng)
-        { return -std::log(__urng()) / _M_lambda; }
-
-      /**
-       * Inserts a %exponential_distribution random number distribution
-       * @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %exponential_distribution random number distribution.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _RealType1, typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const exponential_distribution<_RealType1>& __x);
-
-      /**
-       * Extracts a %exponential_distribution random number distribution
-       * @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x A %exponential_distribution random number
-       *            generator engine.
-       *
-       * @returns The input stream with @p __x extracted or in an error state.
-       */
-      template<typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   exponential_distribution& __x)
-        { return __is >> __x._M_lambda; }
-
-    private:
-      result_type _M_lambda;
-    };
-
-
-  /**
-   * @brief A normal continuous distribution for random numbers.
-   *
-   * The formula for the normal probability mass function is 
-   * @f$ p(x) = \frac{1}{\sigma \sqrt{2 \pi}} 
-   *            e^{- \frac{{x - mean}^ {2}}{2 \sigma ^ {2}} } @f$.
-   */
-  template<typename _RealType = double>
-    class normal_distribution
-    {
-    public:
-      // types
-      typedef _RealType input_type;
-      typedef _RealType result_type;
-
-    public:
-      /**
-       * Constructs a normal distribution with parameters @f$ mean @f$ and
-       * @f$ \sigma @f$.
-       */
-      explicit
-      normal_distribution(const result_type& __mean = result_type(0),
-			  const result_type& __sigma = result_type(1))
-      : _M_mean(__mean), _M_sigma(__sigma), _M_saved_available(false)
-      { 
-	_GLIBCXX_DEBUG_ASSERT(_M_sigma > 0);
-      }
-
-      /**
-       * Gets the mean of the distribution.
-       */
-      _RealType
-      mean() const
-      { return _M_mean; }
-
-      /**
-       * Gets the @f$ \sigma @f$ of the distribution.
-       */
-      _RealType
-      sigma() const
-      { return _M_sigma; }
-
-      /**
-       * Resets the distribution.
-       */
-      void
-      reset()
-      { _M_saved_available = false; }
-
-      template<class _UniformRandomNumberGenerator>
-        result_type
-        operator()(_UniformRandomNumberGenerator& __urng);
-
-      /**
-       * Inserts a %normal_distribution random number distribution
-       * @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %normal_distribution random number distribution.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _RealType1, typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const normal_distribution<_RealType1>& __x);
-
-      /**
-       * Extracts a %normal_distribution random number distribution
-       * @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A %normal_distribution random number generator engine.
-       *
-       * @returns The input stream with @p __x extracted or in an error state.
-       */
-      template<typename _RealType1, typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   normal_distribution<_RealType1>& __x);
-
-    private:
-      result_type _M_mean;
-      result_type _M_sigma;
-      result_type _M_saved;
-      bool        _M_saved_available;     
-    };
-
-
-  /**
-   * @brief A gamma continuous distribution for random numbers.
-   *
-   * The formula for the gamma probability mass function is 
-   * @f$ p(x) = \frac{1}{\Gamma(\alpha)} x^{\alpha - 1} e^{-x} @f$.
-   */
-  template<typename _RealType = double>
-    class gamma_distribution
-    {
-    public:
-      // types
-      typedef _RealType input_type;
-      typedef _RealType result_type;
-
-    public:
-      /**
-       * Constructs a gamma distribution with parameters @f$ \alpha @f$.
-       */
-      explicit
-      gamma_distribution(const result_type& __alpha_val = result_type(1))
-      : _M_alpha(__alpha_val)
-      { 
-	_GLIBCXX_DEBUG_ASSERT(_M_alpha > 0);
-	_M_initialize();
-      }
-
-      /**
-       * Gets the @f$ \alpha @f$ of the distribution.
-       */
-      _RealType
-      alpha() const
-      { return _M_alpha; }
-
-      /**
-       * Resets the distribution.
-       */
-      void
-      reset() { }
-
-      template<class _UniformRandomNumberGenerator>
-        result_type
-        operator()(_UniformRandomNumberGenerator& __urng);
-
-      /**
-       * Inserts a %gamma_distribution random number distribution
-       * @p __x into the output stream @p __os.
-       *
-       * @param __os An output stream.
-       * @param __x  A %gamma_distribution random number distribution.
-       *
-       * @returns The output stream with the state of @p __x inserted or in
-       * an error state.
-       */
-      template<typename _RealType1, typename _CharT, typename _Traits>
-        friend std::basic_ostream<_CharT, _Traits>&
-        operator<<(std::basic_ostream<_CharT, _Traits>& __os,
-		   const gamma_distribution<_RealType1>& __x);
-
-      /**
-       * Extracts a %gamma_distribution random number distribution
-       * @p __x from the input stream @p __is.
-       *
-       * @param __is An input stream.
-       * @param __x  A %gamma_distribution random number generator engine.
-       *
-       * @returns The input stream with @p __x extracted or in an error state.
-       */
-      template<typename _CharT, typename _Traits>
-        friend std::basic_istream<_CharT, _Traits>&
-        operator>>(std::basic_istream<_CharT, _Traits>& __is,
-		   gamma_distribution& __x)
-        {
-	  __is >> __x._M_alpha;
-	  __x._M_initialize();
-	  return __is;
-	}
-
-    private:
-      void
-      _M_initialize();
-
-      result_type _M_alpha;
-
-      // Hosts either lambda of GB or d of modified Vaduva's.
-      result_type _M_l_d;
-    };
-
-  /* @} */ // group tr1_random_distributions_continuous
-  /* @} */ // group tr1_random_distributions
-  /* @} */ // group tr1_random
-
-_GLIBCXX_END_NAMESPACE
-}
-
-#include <tr1/random.tcc>
 
-#endif // _TR1_RANDOM
+#endif // _GLIBCXX_TR1_RANDOM