On Thu, 20 Feb 2020, Jonathan Wakely wrote:
> On 19/02/20 23:53 -0500, Patrick Palka wrote:
> > We are forwarding the second argument of views::iota using the wrong type,
> > causing compiling errors when calling it with a value and bound of different
> > types, like in the test case below.
>
> Good catch, OK for master.
Oops, the second patch in this series includes a friendship change that
should instead be a part of this patch: iota_view::_Iterator must
befriend iota_view::_Sentinel, so that iota_view::_Sentinel::operator==
can access its private members. This is needed for the new test in
iota_view.cc to compile.
Tested on x86_64-pc-linux-gnu, does this look OK to commit?
-- >8 --
Subject: [PATCH] libstdc++: Forward second argument of views::iota using the
correct type
We are forwarding the second argument of views::iota using the wrong type,
causing compile errors when calling views::iota with a value and bound of
different types, like in the test case below.
libstdc++-v3/ChangeLog:
* include/std/ranges (iota_view): Forward declare _Sentinel.
(iota_view::_Iterator): Befriend _Sentinel.
(iota_view::_Sentinel::_M_equal): New member function.
(iota_view::_Sentinel::operator==): Use it.
(views::_Iota::operator()): Forward __f using the correct type.
* testsuite/std/ranges/access/ssize.cc (test06): Don't call views::iota
with integers of different signedness, to appease iota_view's deduction
guide.
* testsuite/std/ranges/iota/iota_view.cc: Augment test.
---
libstdc++-v3/ChangeLog | 9 +++++++++
libstdc++-v3/include/std/ranges | 12 ++++++++++--
.../testsuite/std/ranges/access/ssize.cc | 2 +-
.../testsuite/std/ranges/iota/iota_view.cc | 17 +++++++++++++++++
4 files changed, 37 insertions(+), 3 deletions(-)
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 30cf706cdae..90098fa9aa5 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,12 @@
+2020-02-20 Patrick Palka <ppa...@redhat.com>
+
+ * include/std/ranges (views::_Iota::operator()): Forward __f using the
+ correct type.
+ * testsuite/std/ranges/access/ssize.cc (test06): Don't call views::iota
+ with integers of different signedness, to appease iota_view's deduction
+ guide.
+ * testsuite/std/ranges/iota/iota_view.cc: Augment test.
+
2020-02-20 Jonathan Wakely <jwak...@redhat.com>
* include/bits/range_access.h (ranges::begin): Reject array of
diff --git a/libstdc++-v3/include/std/ranges b/libstdc++-v3/include/std/ranges
index 7a66491f2e4..6358ce86f79 100644
--- a/libstdc++-v3/include/std/ranges
+++ b/libstdc++-v3/include/std/ranges
@@ -635,6 +635,8 @@ namespace ranges
class iota_view : public view_interface<iota_view<_Winc, _Bound>>
{
private:
+ struct _Sentinel;
+
struct _Iterator
{
private:
@@ -811,11 +813,17 @@ namespace ranges
private:
_Winc _M_value = _Winc();
+
+ friend _Sentinel;
};
struct _Sentinel
{
private:
+ constexpr bool
+ _M_equal(const _Iterator& __x) const
+ { return __x._M_value == _M_bound; }
+
_Bound _M_bound = _Bound();
public:
@@ -827,7 +835,7 @@ namespace ranges
friend constexpr bool
operator==(const _Iterator& __x, const _Sentinel& __y)
- { return __x._M_value == __y._M_bound; }
+ { return __y._M_equal(__x); }
friend constexpr iter_difference_t<_Winc>
operator-(const _Iterator& __x, const _Sentinel& __y)
@@ -933,7 +941,7 @@ namespace views
template<typename _Tp, typename _Up>
constexpr auto
operator()(_Tp&& __e, _Up&& __f) const
- { return iota_view{std::forward<_Tp>(__e), std::forward<_Tp>(__f)}; }
+ { return iota_view{std::forward<_Tp>(__e), std::forward<_Up>(__f)}; }
};
inline constexpr _Iota iota{};
diff --git a/libstdc++-v3/testsuite/std/ranges/access/ssize.cc
b/libstdc++-v3/testsuite/std/ranges/access/ssize.cc
index 6f5478e2bb1..8423654c5f7 100644
--- a/libstdc++-v3/testsuite/std/ranges/access/ssize.cc
+++ b/libstdc++-v3/testsuite/std/ranges/access/ssize.cc
@@ -75,7 +75,7 @@ test05()
void
test06()
{
- auto i = std::views::iota(1ull, 5);
+ auto i = std::views::iota(1ull, 5u);
auto s = std::ranges::ssize(i);
using R = std::ranges::range_difference_t<decltype(i)>;
static_assert( std::same_as<decltype(s), R> );
diff --git a/libstdc++-v3/testsuite/std/ranges/iota/iota_view.cc
b/libstdc++-v3/testsuite/std/ranges/iota/iota_view.cc
index 798e745d3f0..65d166fbd3b 100644
--- a/libstdc++-v3/testsuite/std/ranges/iota/iota_view.cc
+++ b/libstdc++-v3/testsuite/std/ranges/iota/iota_view.cc
@@ -61,10 +61,27 @@ test03()
VERIFY( it == v.end() );
}
+void
+test04()
+{
+ int x[] = {1,2,3};
+ auto v = std::ranges::views::iota(std::counted_iterator(x, 3),
+ std::default_sentinel);
+ auto it = v.begin();
+ VERIFY( (*it).base() == x );
+ ++it;
+ VERIFY( (*it).base() == x+1 );
+ ++it;
+ VERIFY( (*it).base() == x+2 );
+ ++it;
+ VERIFY( it == v.end() );
+}
+
int
main()
{
test01();
test02();
test03();
+ test04();
}
--
2.25.1.291.ge68e29171c
