On 30/03/14 12:54 +0200, Lars Gullik Bjønnes wrote:
When trying to convert some code using boost::optional to using
std::experimental::optional instead if come over the issue that I had to
implement operator!= for the contained types.
When looking at n3793 it states that operator!= should be implemented
with !(t1 == t2), and not t1 != t2 as the implementation in gcc 4.9 is
doing. This is the case for both the operator!= implementation where
optional<T> is compared against T.
The other operators look ok, and only operator== and operator< are used
in their implementations.
Can this be fixed before 4.9?
I've committed the patch from PR 60710 (attached) and will apply it to
the 4.9 branch too.
Tested x86_64-linux.
commit ca00614d7bca5305905073dd558c6efacfb029ad
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Fri Apr 25 20:16:05 2014 +0100
2014-04-25 Lars Gullik Bjønnes <lar...@gullik.org>
PR libstdc++/60710
* include/experimental/optional (operator!=): Implement in terms of
operator==.
* testsuite/experimental/optional/relops/1.cc: Remove operator!=.
* testsuite/experimental/optional/relops/2.cc: Likewise.
* testsuite/experimental/optional/relops/3.cc: Likewise.
* testsuite/experimental/optional/relops/4.cc: Likewise.
* testsuite/experimental/optional/relops/5.cc: Likewise.
* testsuite/experimental/optional/relops/6.cc: Likewise.
diff --git a/libstdc++-v3/include/experimental/optional b/libstdc++-v3/include/experimental/optional
index 5f2d93f..2a3f29d 100644
--- a/libstdc++-v3/include/experimental/optional
+++ b/libstdc++-v3/include/experimental/optional
@@ -736,12 +736,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _Tp>
constexpr bool
operator!=(const optional<_Tp>& __lhs, _Tp const& __rhs)
- { return !__lhs || *__lhs != __rhs; }
+ { return !__lhs || !(*__lhs == __rhs); }
template<typename _Tp>
constexpr bool
operator!=(const _Tp& __lhs, const optional<_Tp>& __rhs)
- { return !__rhs || __lhs != *__rhs; }
+ { return !__rhs || !(__lhs == *__rhs); }
template<typename _Tp>
constexpr bool
diff --git a/libstdc++-v3/testsuite/experimental/optional/relops/1.cc b/libstdc++-v3/testsuite/experimental/optional/relops/1.cc
index f140880..3f1ee9c 100644
--- a/libstdc++-v3/testsuite/experimental/optional/relops/1.cc
+++ b/libstdc++-v3/testsuite/experimental/optional/relops/1.cc
@@ -37,10 +37,6 @@ namespace ns
{ return std::tie(lhs.i, lhs.s) == std::tie(rhs.i, rhs.s); }
bool
- operator!=(value_type const& lhs, value_type const& rhs)
- { return !(lhs == rhs); }
-
- bool
operator<(value_type const& lhs, value_type const& rhs)
{ return std::tie(lhs.i, lhs.s) < std::tie(rhs.i, rhs.s); }
diff --git a/libstdc++-v3/testsuite/experimental/optional/relops/2.cc b/libstdc++-v3/testsuite/experimental/optional/relops/2.cc
index c7fc848..6ee9cba 100644
--- a/libstdc++-v3/testsuite/experimental/optional/relops/2.cc
+++ b/libstdc++-v3/testsuite/experimental/optional/relops/2.cc
@@ -37,10 +37,6 @@ namespace ns
{ return std::tie(lhs.i, lhs.s) == std::tie(rhs.i, rhs.s); }
bool
- operator!=(value_type const& lhs, value_type const& rhs)
- { return !(lhs == rhs); }
-
- bool
operator<(value_type const& lhs, value_type const& rhs)
{ return std::tie(lhs.i, lhs.s) < std::tie(rhs.i, rhs.s); }
diff --git a/libstdc++-v3/testsuite/experimental/optional/relops/3.cc b/libstdc++-v3/testsuite/experimental/optional/relops/3.cc
index 9729000..581d016 100644
--- a/libstdc++-v3/testsuite/experimental/optional/relops/3.cc
+++ b/libstdc++-v3/testsuite/experimental/optional/relops/3.cc
@@ -37,10 +37,6 @@ namespace ns
{ return std::tie(lhs.i, lhs.s) == std::tie(rhs.i, rhs.s); }
bool
- operator!=(value_type const& lhs, value_type const& rhs)
- { return !(lhs == rhs); }
-
- bool
operator<(value_type const& lhs, value_type const& rhs)
{ return std::tie(lhs.i, lhs.s) < std::tie(rhs.i, rhs.s); }
diff --git a/libstdc++-v3/testsuite/experimental/optional/relops/4.cc b/libstdc++-v3/testsuite/experimental/optional/relops/4.cc
index 45378f6..ce16fcb 100644
--- a/libstdc++-v3/testsuite/experimental/optional/relops/4.cc
+++ b/libstdc++-v3/testsuite/experimental/optional/relops/4.cc
@@ -37,10 +37,6 @@ namespace ns
{ return std::tie(lhs.i, lhs.s) == std::tie(rhs.i, rhs.s); }
bool
- operator!=(value_type const& lhs, value_type const& rhs)
- { return !(lhs == rhs); }
-
- bool
operator<(value_type const& lhs, value_type const& rhs)
{ return std::tie(lhs.i, lhs.s) < std::tie(rhs.i, rhs.s); }
diff --git a/libstdc++-v3/testsuite/experimental/optional/relops/5.cc b/libstdc++-v3/testsuite/experimental/optional/relops/5.cc
index 008409e..c01bba5 100644
--- a/libstdc++-v3/testsuite/experimental/optional/relops/5.cc
+++ b/libstdc++-v3/testsuite/experimental/optional/relops/5.cc
@@ -37,10 +37,6 @@ namespace ns
{ return std::tie(lhs.i, lhs.s) == std::tie(rhs.i, rhs.s); }
bool
- operator!=(value_type const& lhs, value_type const& rhs)
- { return !(lhs == rhs); }
-
- bool
operator<(value_type const& lhs, value_type const& rhs)
{ return std::tie(lhs.i, lhs.s) < std::tie(rhs.i, rhs.s); }
diff --git a/libstdc++-v3/testsuite/experimental/optional/relops/6.cc b/libstdc++-v3/testsuite/experimental/optional/relops/6.cc
index b179140..a24622b 100644
--- a/libstdc++-v3/testsuite/experimental/optional/relops/6.cc
+++ b/libstdc++-v3/testsuite/experimental/optional/relops/6.cc
@@ -37,10 +37,6 @@ namespace ns
{ return std::tie(lhs.i, lhs.s) == std::tie(rhs.i, rhs.s); }
bool
- operator!=(value_type const& lhs, value_type const& rhs)
- { return !(lhs == rhs); }
-
- bool
operator<(value_type const& lhs, value_type const& rhs)
{ return std::tie(lhs.i, lhs.s) < std::tie(rhs.i, rhs.s); }
