commit 9cd4eeefcc641dd70d026e08e9d218101b826c52
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Mon Feb 17 15:25:33 2020 +0000
libstdc++: Reduce header dependencies for C++20 (PR 92546)
In C++20 <memory> depends on <bits/ranges_unitialized.h> which
depends on <bits/random.h> just for a single concept. Including
<bits/random.h> also requires including <cmath>, which is huge due to
the C++17 special functions.
This change moves the concept to the <bits/uniform_int_dist.h> internal
header that exists so that <bits/stl_algobase.h> doesn't need to include
<bits/random.h>.
PR libstdc++/92546 (partial)
* include/bits/random.h (uniform_random_bit_generator): Move definition
to <bits/uniform_int_dist.h>.
* include/bits/ranges_algo.h: Include <bits/uniform_int_dist.h> instead
of <bits/random.h>.
* include/bits/ranges_algobase.h: Do not include <cmath>.
* include/bits/uniform_int_dist.h (uniform_random_bit_generator):
Move here.
* include/std/ranges: Do not include <limits>.
* testsuite/26_numerics/random/pr60037-neg.cc: Adjust dg-error lineno.
@@ -33,9 +33,6 @@
#include <vector>
#include <bits/uniform_int_dist.h>
-#if __cplusplus > 201703L
-# include <concepts>
-#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
@@ -51,18 +48,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
* @{
*/
-#ifdef __cpp_lib_concepts
- /// Requirements for a uniform random bit generator.
- template<typename _Gen>
- concept uniform_random_bit_generator
- = invocable<_Gen&> && unsigned_integral<invoke_result_t<_Gen&>>
- && requires
- {
- { _Gen::min() } -> same_as<invoke_result_t<_Gen&>>;
- { _Gen::max() } -> same_as<invoke_result_t<_Gen&>>;
- requires bool_constant<(_Gen::min() < _Gen::max())>::value;
- };
-#endif
+ // std::uniform_random_bit_generator is defined in <bits/uniform_int_dist.h>
/**
* @brief A function template for converting the output of a (integral)
@@ -33,7 +33,7 @@
#if __cplusplus > 201703L
#include <bits/ranges_algobase.h>
-#include <bits/random.h> // concept uniform_random_bit_generator
+#include <bits/uniform_int_dist.h> // concept uniform_random_bit_generator
#if __cpp_lib_concepts
namespace std _GLIBCXX_VISIBILITY(default)
@@ -32,7 +32,6 @@
#if __cplusplus > 201703L
-#include <cmath>
#include <compare>
#include <iterator>
// #include <bits/range_concepts.h>
@@ -33,11 +33,27 @@
#include <type_traits>
#include <limits>
+#if __cplusplus > 201703L
+# include <concepts>
+#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
+#ifdef __cpp_lib_concepts
+ /// Requirements for a uniform random bit generator.
+ template<typename _Gen>
+ concept uniform_random_bit_generator
+ = invocable<_Gen&> && unsigned_integral<invoke_result_t<_Gen&>>
+ && requires
+ {
+ { _Gen::min() } -> same_as<invoke_result_t<_Gen&>>;
+ { _Gen::max() } -> same_as<invoke_result_t<_Gen&>>;
+ requires bool_constant<(_Gen::min() < _Gen::max())>::value;
+ };
+#endif
+
namespace __detail
{
/* Determine whether number is a power of 2. */
@@ -42,7 +42,6 @@
#include <compare>
#include <initializer_list>
#include <iterator>
-#include <limits>
#include <optional>
#include <tuple>
@@ -10,6 +10,6 @@ std::__detail::_Adaptor<std::mt19937, unsigned long> aurng(urng);
auto x = std::generate_canonical<std::size_t,
std::numeric_limits<std::size_t>::digits>(urng);
-// { dg-error "static assertion failed: template argument must be a floating point type" "" { target *-*-* } 172 }
+// { dg-error "static assertion failed: template argument must be a floating point type" "" { target *-*-* } 158 }
// { dg-error "static assertion failed: template argument must be a floating point type" "" { target *-*-* } 3281 }