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Fix: prevented the binding illegal temporary to optional<const int&>

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Older MSVC versions add illegal temporary when you want to assign from const integral value.
This commit is contained in:
Andrzej Krzemienski
2016-02-18 23:18:01 +01:00
parent 1671966380
commit 44d57a1d8b
20 changed files with 161 additions and 109 deletions
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2
doc/11_development.qbk
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@ -228,7 +228,7 @@ For value access operations `optional<>` uses operators `*` and `->` to
lexically warn about the possibly uninitialized state appealing to the
familiar pointer semantics w.r.t. to null pointers.
[warning
[caution
However, it is particularly important to note that `optional<>` objects
are not pointers. [_`optional<>` is not, and does not model, a pointer].
]

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doc/15_optional_references.qbk
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@ -1,6 +1,8 @@

[section Optional references]
[section Overview]
This library allows the template parameter `T` to be of reference type:
`T&`, and to some extent, `T const&`.
@ -21,7 +23,7 @@ will nonetheless refer to the same object.
* Value-access will actually provide access to the referenced object
rather than the reference itself.
[warning On compilers that do not conform to Standard C++ rules of reference binding, operations on optional references might give adverse results: rather than binding a reference to a designated object they may create an unexpected temporary and bind to it. For more details see [link boost_optional.dependencies_and_portability.optional_reference_binding Dependencies and Portability section].]
[caution On compilers that do not conform to Standard C++ rules of reference binding, some operations on optional references are disabled in order to prevent subtle bugs. For more details see [link boost_optional.dependencies_and_portability.optional_reference_binding Dependencies and Portability section].]
[heading Rvalue references]
@ -118,3 +120,4 @@ In such a scenario, you can assign the value itself directly, as in:
*opt=value;
[endsect]
[endsect]

2
doc/28_ref_optional_semantics.qbk
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@ -857,7 +857,7 @@ __SPACE__
* [*Postconditions:] `bool(*this) == bool(rhs)`.
* [*Notes:] This behaviour is called ['rebinding semantics]. See [link boost_optional.tutorial.rebinding_semantics_for_assignment_of_optional_references here] for details.
* [*Notes:] This behaviour is called ['rebinding semantics]. See [link boost_optional.tutorial.optional_references.rebinding_semantics_for_assignment_of_optional_references here] for details.
* [*Example:]
``

8
doc/90_dependencies.qbk
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@ -30,17 +30,17 @@ The implementation uses the following other Boost modules:
[section Optional Reference Binding]
On compilers that do not conform to Standard C++ rules of reference binding, operations on optional references might give adverse results: rather than binding a reference to a designated object they may create an unexpected temporary and bind to it. Compilers known to have these deficiencies include GCC versions 4.2, 4.3, 4.4, 4.5; QCC 4.4.2; MSVC versions 8.0, 9.0, 10.0, 11.0, 12.0. On these compilers prefer using direct-initialization and copy assignment of optional references to copy-initialization and assignment from `T&`:
A number of compilers incorrectly treat const lvalues of integral type as rvalues, and create an illegal temporary when binding to an lvalue reference to const in some expressions. This could result in creating an optional lvalue reference that is in fact bound to an unexpected temporary rather than to the intended object. In order to prevent hard to find run-time bugs, this library performs compile-time checks to prevent expressions that would otherwise bind an optional reference to an unexpected temporary. As a consequence, on certain compilers certain pieces of functionality in optional references are missing. In order to maintain a portability of your code across diferent compilers, it is recommended that you only stick to the minimum portable interface of optional references: prefer direct-initialization and copy assignment of optional references to copy-initialization and assignment from `T&`:
const int i = 0;
optional<const int&> or1;
optional<const int&> or2 = i; // not portable
or1 = i; // not portable
optional<const int&> or2 = i; // caution: not portable
or1 = i; // caution: not portable
optional<const int&> or3(i); // portable
or1 = optional<const int&>(i); // portable
In order to check if your compiler correctly implements reference binding use this test program.
Compilers known to have these deficiencies include GCC versions 4.2, 4.3, 4.4, 4.5, 5.1, 5.2; QCC 4.4.2; MSVC versions 8.0, 9.0, 10.0, 11.0, 12.0. In order to check if your compiler correctly implements reference binding use this test program.
#include <cassert>

1
doc/91_relnotes.qbk
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@ -16,6 +16,7 @@
* Now `boost::optional` is specialized for reference parameters. This addresses a couple of issues:
* the `sizeof` of optional reference is that of a pointer,
* some bugs connected to copying optional references are gone,
* all run-time bugs caused by incorrect reference binding on some compilers are now turned into compile-time errors,
* you can swap optional references: it is like swapping pointers: shalow, underlying objects are not affected,
* optional references to abstract types work.
* Documented nested typedefs ([@https://svn.boost.org/trac/boost/ticket/5193 Trac #5193]).

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doc/html/boost_optional/dependencies_and_portability/optional_reference_binding.html
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@ -28,24 +28,30 @@
Reference Binding</a>
</h3></div></div></div>
<p>
On compilers that do not conform to Standard C++ rules of reference binding,
operations on optional references might give adverse results: rather than
binding a reference to a designated object they may create an unexpected
temporary and bind to it. Compilers known to have these deficiencies include
GCC versions 4.2, 4.3, 4.4, 4.5; QCC 4.4.2; MSVC versions 8.0, 9.0, 10.0,
11.0, 12.0. On these compilers prefer using direct-initialization and copy
assignment of optional references to copy-initialization and assignment from
<code class="computeroutput"><span class="identifier">T</span><span class="special">&amp;</span></code>:
A number of compilers incorrectly treat const lvalues of integral type as
rvalues, and create an illegal temporary when binding to an lvalue reference
to const in some expressions. This could result in creating an optional lvalue
reference that is in fact bound to an unexpected temporary rather than to
the intended object. In order to prevent hard to find run-time bugs, this
library performs compile-time checks to prevent expressions that would otherwise
bind an optional reference to an unexpected temporary. As a consequence,
on certain compilers certain pieces of functionality in optional references
are missing. In order to maintain a portability of your code across diferent
compilers, it is recommended that you only stick to the minimum portable
interface of optional references: prefer direct-initialization and copy assignment
of optional references to copy-initialization and assignment from <code class="computeroutput"><span class="identifier">T</span><span class="special">&amp;</span></code>:
</p>
<pre class="programlisting"><span class="keyword">const</span> <span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">0</span><span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">or1</span><span class="special">;</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">or2</span> <span class="special">=</span> <span class="identifier">i</span><span class="special">;</span> <span class="comment">// not portable</span>
<span class="identifier">or1</span> <span class="special">=</span> <span class="identifier">i</span><span class="special">;</span> <span class="comment">// not portable</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">or2</span> <span class="special">=</span> <span class="identifier">i</span><span class="special">;</span> <span class="comment">// caution: not portable</span>
<span class="identifier">or1</span> <span class="special">=</span> <span class="identifier">i</span><span class="special">;</span> <span class="comment">// caution: not portable</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">or3</span><span class="special">(</span><span class="identifier">i</span><span class="special">);</span> <span class="comment">// portable</span>
<span class="identifier">or1</span> <span class="special">=</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">int</span><span class="special">&amp;&gt;(</span><span class="identifier">i</span><span class="special">);</span> <span class="comment">// portable</span>
</pre>
<p>
Compilers known to have these deficiencies include GCC versions 4.2, 4.3,
4.4, 4.5, 5.1, 5.2; QCC 4.4.2; MSVC versions 8.0, 9.0, 10.0, 11.0, 12.0.
In order to check if your compiler correctly implements reference binding
use this test program.
</p>

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@ -189,7 +189,7 @@
</li>
<li class="listitem">
<span class="bold"><strong>Notes:</strong></span> This behaviour is called <span class="emphasis"><em>rebinding
semantics</em></span>. See <a class="link" href="../../tutorial/rebinding_semantics_for_assignment_of_optional_references.html" title="Rebinding semantics for assignment of optional references">here</a>
semantics</em></span>. See <a class="link" href="../../tutorial/optional_references/rebinding_semantics_for_assignment_of_optional_references.html" title="Rebinding semantics for assignment of optional references">here</a>
for details.
</li>
<li class="listitem">

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@ -43,6 +43,10 @@
<li class="listitem">
some bugs connected to copying optional references are gone,
</li>
<li class="listitem">
all run-time bugs caused by incorrect reference binding on some compilers
are now turned into compile-time errors,
</li>
<li class="listitem">
you can swap optional references: it is like swapping pointers: shalow,
underlying objects are not affected,

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@ -142,10 +142,10 @@
about the possibly uninitialized state appealing to the familiar pointer
semantics w.r.t. to null pointers.
</p>
<div class="warning"><table border="0" summary="Warning">
<div class="caution"><table border="0" summary="Caution">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Warning]" src="../../../../../../../doc/src/images/warning.png"></td>
<th align="left">Warning</th>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="../../../../../../../doc/src/images/caution.png"></td>
<th align="left">Caution</th>
</tr>
<tr><td align="left" valign="top"><p>
However, it is particularly important to note that <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;&gt;</span></code> objects are not pointers. <span class="underline"><code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;&gt;</span></code> is not, and does not model, a

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@ -6,7 +6,7 @@
<meta name="generator" content="DocBook XSL Stylesheets V1.78.1">
<link rel="home" href="../../index.html" title="Boost.Optional">
<link rel="up" href="../../optional/tutorial.html" title="Tutorial">
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@ -20,7 +20,7 @@
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@ -191,7 +191,7 @@
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@ -7,7 +7,7 @@
<link rel="home" href="../../index.html" title="Boost.Optional">
<link rel="up" href="../../optional/tutorial.html" title="Tutorial">
<link rel="prev" href="io_operators.html" title="IO operators">
<link rel="next" href="rebinding_semantics_for_assignment_of_optional_references.html" title="Rebinding semantics for assignment of optional references">
<link rel="next" href="optional_references/rebinding_semantics_for_assignment_of_optional_references.html" title="Rebinding semantics for assignment of optional references">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table cellpadding="2" width="100%"><tr>
@ -20,85 +20,87 @@
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<a accesskey="p" href="io_operators.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../optional/tutorial.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="rebinding_semantics_for_assignment_of_optional_references.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a>
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</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_optional.tutorial.optional_references"></a><a class="link" href="optional_references.html" title="Optional references">Optional
references</a>
</h3></div></div></div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="boost_optional.tutorial.optional_references.overview"></a><a class="link" href="optional_references.html#boost_optional.tutorial.optional_references.overview" title="Overview">Overview</a>
</h4></div></div></div>
<p>
This library allows the template parameter <code class="computeroutput"><span class="identifier">T</span></code>
to be of reference type: <code class="computeroutput"><span class="identifier">T</span><span class="special">&amp;</span></code>, and to some extent, <code class="computeroutput"><span class="identifier">T</span>
<span class="keyword">const</span><span class="special">&amp;</span></code>.
</p>
This library allows the template parameter <code class="computeroutput"><span class="identifier">T</span></code>
to be of reference type: <code class="computeroutput"><span class="identifier">T</span><span class="special">&amp;</span></code>, and to some extent, <code class="computeroutput"><span class="identifier">T</span> <span class="keyword">const</span><span class="special">&amp;</span></code>.
</p>
<p>
However, since references are not real objects some restrictions apply and
some operations are not available in this case:
</p>
However, since references are not real objects some restrictions apply
and some operations are not available in this case:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
Converting constructors
</li>
Converting constructors
</li>
<li class="listitem">
Converting assignment
</li>
Converting assignment
</li>
<li class="listitem">
InPlace construction
</li>
InPlace construction
</li>
<li class="listitem">
InPlace assignment
</li>
InPlace assignment
</li>
<li class="listitem">
Value-access via pointer
</li>
Value-access via pointer
</li>
</ul></div>
<p>
Also, even though <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span></code>
treats it wrapped pseudo-object much as a real value, a true real reference
is stored so aliasing will ocurr:
</p>
Also, even though <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span></code> treats it wrapped pseudo-object
much as a real value, a true real reference is stored so aliasing will
ocurr:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
Copies of <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span></code>
will copy the references but all these references will nonetheless refer
to the same object.
</li>
Copies of <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&amp;&gt;</span></code> will copy the references but
all these references will nonetheless refer to the same object.
</li>
<li class="listitem">
Value-access will actually provide access to the referenced object rather
than the reference itself.
</li>
Value-access will actually provide access to the referenced object
rather than the reference itself.
</li>
</ul></div>
<div class="warning"><table border="0" summary="Warning">
<div class="caution"><table border="0" summary="Caution">
<tr>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Warning]" src="../../../../../../doc/src/images/warning.png"></td>
<th align="left">Warning</th>
<td rowspan="2" align="center" valign="top" width="25"><img alt="[Caution]" src="../../../../../../doc/src/images/caution.png"></td>
<th align="left">Caution</th>
</tr>
<tr><td align="left" valign="top"><p>
On compilers that do not conform to Standard C++ rules of reference binding,
operations on optional references might give adverse results: rather than
binding a reference to a designated object they may create an unexpected
temporary and bind to it. For more details see <a class="link" href="../dependencies_and_portability/optional_reference_binding.html" title="Optional Reference Binding">Dependencies
and Portability section</a>.
</p></td></tr>
On compilers that do not conform to Standard C++ rules of reference binding,
some operations on optional references are disabled in order to prevent
subtle bugs. For more details see <a class="link" href="../dependencies_and_portability/optional_reference_binding.html" title="Optional Reference Binding">Dependencies
and Portability section</a>.
</p></td></tr>
</table></div>
<h5>
<a name="boost_optional.tutorial.optional_references.h0"></a>
<span class="phrase"><a name="boost_optional.tutorial.optional_references.rvalue_references"></a></span><a class="link" href="optional_references.html#boost_optional.tutorial.optional_references.rvalue_references">Rvalue
references</a>
</h5>
<h6>
<a name="boost_optional.tutorial.optional_references.overview.h0"></a>
<span class="phrase"><a name="boost_optional.tutorial.optional_references.overview.rvalue_references"></a></span><a class="link" href="optional_references.html#boost_optional.tutorial.optional_references.overview.rvalue_references">Rvalue
references</a>
</h6>
<p>
Rvalue references and lvalue references to const have the ability in C++
to extend the life time of a temporary they bind to. Optional references
do not have this capability, therefore to avoid surprising effects it is
not possible to initialize an optional references from a temporary. Optional
rvalue references are disabled altogether. Also, the initialization and assignment
of an optional reference to const from rvalue reference is disabled.
</p>
Rvalue references and lvalue references to const have the ability in C++
to extend the life time of a temporary they bind to. Optional references
do not have this capability, therefore to avoid surprising effects it is
not possible to initialize an optional references from a temporary. Optional
rvalue references are disabled altogether. Also, the initialization and
assignment of an optional reference to const from rvalue reference is disabled.
</p>
<pre class="programlisting"><span class="keyword">const</span> <span class="keyword">int</span><span class="special">&amp;</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">1</span><span class="special">;</span> <span class="comment">// legal</span>
<span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">int</span><span class="special">&amp;&gt;</span> <span class="identifier">oi</span> <span class="special">=</span> <span class="number">1</span><span class="special">;</span> <span class="comment">// illegal</span>
</pre>
</div>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2016 Andrzej Krzemie&#324;ski<p>
@ -109,7 +111,7 @@
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@ -62,8 +62,6 @@
<dt><span class="section"><a href="boost_optional/tutorial/io_operators.html">IO operators</a></span></dt>
<dt><span class="section"><a href="boost_optional/tutorial/optional_references.html">Optional
references</a></span></dt>
<dt><span class="section"><a href="boost_optional/tutorial/rebinding_semantics_for_assignment_of_optional_references.html">Rebinding
semantics for assignment of optional references</a></span></dt>
<dt><span class="section"><a href="boost_optional/tutorial/in_place_factories.html">In-Place
Factories</a></span></dt>
<dt><span class="section"><a href="boost_optional/tutorial/a_note_about_optional_bool_.html">A
@ -146,7 +144,7 @@
</div>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"><p><small>Last revised: February 16, 2016 at 22:59:47 GMT</small></p></td>
<td align="left"><p><small>Last revised: February 18, 2016 at 23:24:54 GMT</small></p></td>
<td align="right"><div class="copyright-footer"></div></td>
</tr></table>
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@ -36,8 +36,6 @@
<dt><span class="section"><a href="../boost_optional/tutorial/io_operators.html">IO operators</a></span></dt>
<dt><span class="section"><a href="../boost_optional/tutorial/optional_references.html">Optional
references</a></span></dt>
<dt><span class="section"><a href="../boost_optional/tutorial/rebinding_semantics_for_assignment_of_optional_references.html">Rebinding
semantics for assignment of optional references</a></span></dt>
<dt><span class="section"><a href="../boost_optional/tutorial/in_place_factories.html">In-Place
Factories</a></span></dt>
<dt><span class="section"><a href="../boost_optional/tutorial/a_note_about_optional_bool_.html">A

28
include/boost/optional/detail/optional_reference_spec.hpp
View File

@ -12,6 +12,11 @@
#ifndef BOOST_OPTIONAL_DETAIL_OPTIONAL_REFERENCE_SPEC_AJK_03OCT2015_HPP
#define BOOST_OPTIONAL_DETAIL_OPTIONAL_REFERENCE_SPEC_AJK_03OCT2015_HPP
#ifdef BOOST_OPTIONAL_CONFIG_NO_PROPER_ASSIGN_FROM_CONST_INT
#include <boost/type_traits/is_integral.hpp>
#include <boost/type_traits/is_const.hpp>
#endif
# if 1
namespace boost {
@ -39,6 +44,19 @@ BOOST_DEDUCED_TYPENAME boost::remove_reference<T>::type& forward_reference(T&& r
#endif // BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
template <class From>
void prevent_assignment_from_false_const_integral()
{
#ifndef BOOST_OPTIONAL_CONFIG_ALLOW_BINDING_TO_RVALUES
#ifdef BOOST_OPTIONAL_CONFIG_NO_PROPER_ASSIGN_FROM_CONST_INT
// MSVC compiler without rvalue refernces: we need to disable the asignment from
// const integral lvalue reference, as it may be an invalid temporary
BOOST_STATIC_ASSERT_MSG(!(boost::is_const<From>::value && boost::is_integral<From>::value),
"binding const lvalue references to integral types is disabled in this compiler");
#endif
#endif
}
template <class T>
struct is_optional_
{
@ -140,11 +158,15 @@ public:
template <class U>
optional(bool cond, U& v, BOOST_DEDUCED_TYPENAME boost::enable_if<detail::is_no_optional<U> >::type* = 0) BOOST_NOEXCEPT : ptr_(cond ? boost::addressof(v) : 0) {}
template <class U>
BOOST_DEDUCED_TYPENAME boost::enable_if<detail::is_no_optional<U>, optional<T&>&>::type
operator=(U& v) BOOST_NOEXCEPT { ptr_ = boost::addressof(v); return *this; }
operator=(U& v) BOOST_NOEXCEPT
{
detail::prevent_assignment_from_false_const_integral<U>();
ptr_ = boost::addressof(v); return *this;
}
template <class U>
void emplace(U& v, BOOST_DEDUCED_TYPENAME boost::enable_if<detail::is_no_optional<U> >::type* = 0) BOOST_NOEXCEPT
{ ptr_ = boost::addressof(v); }

1
test/Jamfile.v2
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@ -39,6 +39,7 @@ import testing ;
[ run optional_test_emplace.cpp ]
[ run optional_test_minimum_requirements.cpp ]
[ run optional_test_msvc_bug_workaround.cpp ]
[ compile-fail optional_test_ref_convert_assign_const_int_prevented.cpp ]
[ compile-fail optional_test_fail1.cpp ]
[ compile-fail optional_test_fail3a.cpp ]
[ compile-fail optional_test_fail3b.cpp ]

20
test/optional_ref_assign_test_defs.hpp
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@ -163,26 +163,11 @@ void test_rebinding_assignment_semantics()
BOOST_TEST_EQ(val(v), 2);
}
template <typename T>
template <typename T, typename U>
void test_converting_assignment()
{
typename concrete_type_of<T>::type v1(1), v2(2), v3(3);
optional<T&> oA(v1), oB(none);
oA = v2;
BOOST_TEST(oA);
BOOST_TEST(addressof(*oA) == addressof(v2));
oB = v3;
BOOST_TEST(oB);
BOOST_TEST(addressof(*oB) == addressof(v3));
}
template <typename T>
void test_converting_assignment_for_noconst_const()
{
typename concrete_type_of<T>::type v1(1), v2(2), v3(3);
optional<const T&> oA(v1), oB(none);
optional<U&> oA(v1), oB(none);
oA = v2;
BOOST_TEST(oA);
@ -194,4 +179,3 @@ void test_converting_assignment_for_noconst_const()
}
#endif //BOOST_OPTIONAL_TEST_OPTIONAL_REF_ASSIGN_TEST_DEFS_AK_07JAN2015_HPP

6
test/optional_test_ref_convert_assign_const_int.cpp
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@ -23,8 +23,8 @@
int main()
{
test_converting_assignment<const int>();
test_converting_assignment_for_noconst_const<int>();
#ifndef BOOST_OPTIONAL_CONFIG_NO_PROPER_ASSIGN_FROM_CONST_INT
test_converting_assignment<const int, const int>();
#endif
return boost::report_errors();
}

32
test/optional_test_ref_convert_assign_const_int_prevented.cpp Normal file
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@ -0,0 +1,32 @@
// Copyright (C) 2015 Andrzej Krzemienski.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/lib/optional for documentation.
//
// You are welcome to contact the author at: akrzemi1@gmail.com
#include "boost/optional/optional.hpp"
#ifdef __BORLANDC__
#pragma hdrstop
#endif
#include "boost/core/addressof.hpp"
#include "boost/core/enable_if.hpp"
#include "boost/core/lightweight_test.hpp"
#include "testable_classes.hpp"
#include "optional_ref_assign_test_defs.hpp"
int main()
{
#ifdef BOOST_OPTIONAL_CONFIG_NO_PROPER_ASSIGN_FROM_CONST_INT
test_converting_assignment<const int, const int>();
#else
BOOST_STATIC_ASSERT(false, "EXPECTED TEST COMPILE-TIME FAILURE");
#endif
return boost::report_errors();
}

3
test/optional_test_ref_convert_assign_mutable_int.cpp
View File

@ -23,7 +23,8 @@
int main()
{
test_converting_assignment<int>();
test_converting_assignment<int, int>();
test_converting_assignment<int, const int>();
return boost::report_errors();
}

6
test/optional_test_ref_convert_assign_non_int.cpp
View File

@ -25,9 +25,9 @@
template <typename T>
void test_all_const_cases()
{
test_converting_assignment<T>();
test_converting_assignment<const T>();
test_converting_assignment_for_noconst_const<T>();
test_converting_assignment<T, T>();
test_converting_assignment<const T, const T>();
test_converting_assignment<T, const T>();
}
int main()