commit 160dfb8b15ca20581634c235c75293712072f622
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Thu Aug 7 01:13:17 2014 +0100
* acinclude.m4 (GLIBCXX_ENABLE_LIBSTDCXX_CXX11_ABI): Define.
* configure.ac: Use GLIBCXX_ENABLE_LIBSTDCXX_CXX11_ABI.
* configure: Regenerate.
* include/Makefile.am (stamp-cxx11-abi): New target.
(c++config.h): Set _GLIBCXX_USE_CXX11_ABI macro.
* include/Makefile.in: Regenerate.
* include/bits/c++config: Add _GLIBCXX_USE_CXX11_ABI placeholder and
define _GLIBCXX_DEFAULT_ABI_TAG.
* include/bits/list.tcc (list::emplace(const_iterator, _Args&...)):
Increment size.
(list::emplace(const_iterator, const value_type&)): Likewise.
(list::merge(list&), list::merge(list&, _StrictWeakOrdering)): Adjust
list sizes.
* include/bits/stl_list.h (_List_base, list): Add ABI tag macro.
(_List_base::_M_size): New data member in cxx11 ABI mode.
(_List_base::_S_distance(_List_node_base*, _List_node_base*)): New
function.
(_List_base::_M_get_size(), _List_base::_M_set_size(size_t),
_List_base::_M_inc_size(size_t), _List_base::_M_dec_size(size_t),
_List_base::_M_distance, _List_base::_M_node_count): New functions for
accessing list size correctly for the ABI mode.
(_List_base::_List_base(_List_base&&)): Copy size and reset source.
(_List_base::_M_init()): Initialize size member.
(list::size()): Use _List_base::_M_node_count.
(list::swap(list&)): Swap sizes.
(list::splice(iterator, list&)): Update sizes.
(list::splice(iterator, list&, iterator)): Likewise.
(list::insert(iterator, const value_type&)): Update size.
(list::insert(iterator, _Args&&...)): Likewise.
(list::_M_erase(iterator)): Likewise.
* testsuite/23_containers/list/requirements/dr438/assign_neg.cc:
Adjust.
* testsuite/23_containers/list/requirements/dr438/insert_neg.cc:
Adjust.
* testsuite/23_containers/list/requirements/dr438/constructor_2_neg.cc:
Adjust.
* testsuite/23_containers/list/requirements/dr438/constructor_1_neg.cc:
Adjust.
* testsuite/ext/profile/mutex_extensions_neg.cc: Adjust.
@@ -3831,6 +3831,25 @@ AC_DEFUN([GLIBCXX_CHECK_SDT_H], [
AC_MSG_RESULT($glibcxx_cv_sys_sdt_h)
])
+dnl
+dnl Check if the user wants the new C++11-conforming ABI.
+dnl
+dnl --disable-libstdcxx-cxx11-abi will use old ABI for all types.
+dnl
+dnl Defines:
+dnl _GLIBCXX_USE_ABI_TAG (always defined, either to 1 or 0)
+dnl
+AC_DEFUN([GLIBCXX_ENABLE_LIBSTDCXX_CXX11_ABI], [
+ AC_ARG_ENABLE([libstdcxx-cxx11-abi],
+ AC_HELP_STRING([--disable-libstdcxx-cxx11-abi],
+ [disable the C++11-conforming ABI]),,
+ [enable_libstdcxx_cxx11_abi=yes])
+ if test x"$enable_libstdcxx_cxx11_abi" != xyes; then
+ AC_MSG_NOTICE([C++11-conforming ABI is disabled])
+ fi
+ GLIBCXX_CONDITIONAL(ENABLE_CXX11_ABI, test $enable_libstdcxx_cxx11_abi = yes)
+])
+
# Macros from the top-level gcc directory.
m4_include([../config/gc++filt.m4])
m4_include([../config/tls.m4])
@@ -365,6 +365,8 @@ AC_SUBST(libtool_VERSION)
GLIBCXX_ENABLE_LIBSTDCXX_VISIBILITY([yes])
+GLIBCXX_ENABLE_LIBSTDCXX_CXX11_ABI([yes])
+
ac_ldbl_compat=no
case "$target" in
powerpc*-*-linux* | \
@@ -1121,6 +1121,14 @@ stamp-visibility:
echo 0 > stamp-visibility
endif
+if ENABLE_CXX11_ABI
+stamp-cxx11-abi:
+ echo 1 > stamp-cxx11-abi
+else
+stamp-cxx11-abi:
+ echo 0 > stamp-cxx11-abi
+endif
+
# NB: The non-empty default ldbl_compat works around an AIX sed
# oddity, see libstdc++/31957 for details.
${host_builddir}/c++config.h: ${CONFIG_HEADER} \
@@ -1129,11 +1137,13 @@ ${host_builddir}/c++config.h: ${CONFIG_HEADER} \
${toplevel_srcdir}/gcc/DATESTAMP \
stamp-namespace-version \
stamp-visibility \
- stamp-extern-template
+ stamp-extern-template \
+ stamp-cxx11-abi
@date=`cat ${toplevel_srcdir}/gcc/DATESTAMP` ;\
ns_version=`cat stamp-namespace-version` ;\
visibility=`cat stamp-visibility` ;\
externtemplate=`cat stamp-extern-template` ;\
+ cxx11abi=`cat stamp-cxx11-abi` ;\
ldbl_compat='s,g,g,' ;\
grep "^[ ]*#[ ]*define[ ][ ]*_GLIBCXX_LONG_DOUBLE_COMPAT[ ][ ]*1[ ]*$$" \
${CONFIG_HEADER} > /dev/null 2>&1 \
@@ -1142,6 +1152,7 @@ ${host_builddir}/c++config.h: ${CONFIG_HEADER} \
-e "s,define _GLIBCXX_INLINE_VERSION, define _GLIBCXX_INLINE_VERSION $$ns_version," \
-e "s,define _GLIBCXX_HAVE_ATTRIBUTE_VISIBILITY, define _GLIBCXX_HAVE_ATTRIBUTE_VISIBILITY $$visibility," \
-e "s,define _GLIBCXX_EXTERN_TEMPLATE$$, define _GLIBCXX_EXTERN_TEMPLATE $$externtemplate," \
+ -e "s,define _GLIBCXX_USE_CXX11_ABI, define _GLIBCXX_USE_CXX11_ABI $$cxx11abi," \
-e "$$ldbl_compat" \
< ${glibcxx_srcdir}/include/bits/c++config > $@ ;\
sed -e 's/HAVE_/_GLIBCXX_HAVE_/g' \
@@ -193,6 +193,17 @@ namespace std
#endif
}
+// Use abi_tag("cxx11")
+#ifndef _GLIBCXX_USE_CXX11_ABI
+#define _GLIBCXX_USE_CXX11_ABI
+#endif
+
+#if _GLIBCXX_USE_CXX11_ABI
+# define _GLIBCXX_DEFAULT_ABI_TAG _GLIBCXX_ABI_TAG_CXX11
+#else
+# define _GLIBCXX_DEFAULT_ABI_TAG
+#endif
+
// Defined if inline namespaces are used for versioning.
#define _GLIBCXX_INLINE_VERSION
@@ -89,6 +89,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
{
_Node* __tmp = _M_create_node(std::forward<_Args>(__args)...);
__tmp->_M_hook(__position._M_const_cast()._M_node);
+ this->_M_inc_size(1);
return iterator(__tmp);
}
#endif
@@ -104,6 +105,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
{
_Node* __tmp = _M_create_node(__x);
__tmp->_M_hook(__position._M_const_cast()._M_node);
+ this->_M_inc_size(1);
return iterator(__tmp);
}
@@ -353,6 +355,9 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
++__first1;
if (__first2 != __last2)
_M_transfer(__last1, __first2, __last2);
+
+ this->_M_inc_size(__x._M_get_size());
+ __x._M_set_size(0);
}
}
@@ -387,6 +392,9 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
++__first1;
if (__first2 != __last2)
_M_transfer(__last1, __first2, __last2);
+
+ this->_M_inc_size(__x._M_get_size());
+ __x._M_set_size(0);
}
}
@@ -295,7 +295,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
/// See bits/stl_deque.h's _Deque_base for an explanation.
template<typename _Tp, typename _Alloc>
- class _List_base
+ class _GLIBCXX_DEFAULT_ABI_TAG _List_base
{
protected:
// NOTA BENE
@@ -316,11 +316,23 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
typedef typename _Alloc::template rebind<_Tp>::other _Tp_alloc_type;
+ static size_t
+ _S_distance(const __detail::_List_node_base* __first,
+ const __detail::_List_node_base* __last)
+ {
+ size_t __n = 0;
+ while (__first != __last)
+ {
+ __first = __first->_M_next;
+ ++__n;
+ }
+ return __n;
+ }
+
struct _List_impl
: public _Node_alloc_type
{
__detail::_List_node_base _M_node;
-
_List_impl()
: _Node_alloc_type(), _M_node()
{ }
@@ -338,6 +350,40 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_List_impl _M_impl;
+#if _GLIBCXX_USE_CXX11_ABI
+ size_t _M_size;
+
+ size_t _M_get_size() const { return _M_size; }
+
+ void _M_set_size(size_t __n) { _M_size = __n; }
+
+ void _M_inc_size(size_t __n) { _M_size += __n; }
+
+ void _M_dec_size(size_t __n) { _M_size -= __n; }
+
+ size_t
+ _M_distance(const __detail::_List_node_base* __first,
+ const __detail::_List_node_base* __last) const
+ { return _S_distance(__first, __last); }
+
+ // return the stored size
+ size_t _M_node_count() const { return _M_size; }
+#else
+ // dummy implementations used when the size is not stored
+ size_t _M_get_size() const { return 0; }
+ void _M_set_size(size_t) { }
+ void _M_inc_size(size_t) { }
+ void _M_dec_size(size_t) { }
+ size_t _M_distance(const void*, const void*) const { return 0; }
+
+ // count the number of nodes
+ size_t _M_node_count() const
+ {
+ return _S_distance(_M_impl._M_node._M_next,
+ std::__addressof(_M_impl._M_node));
+ }
+#endif
+
_List_node<_Tp>*
_M_get_node()
{ return _M_impl._Node_alloc_type::allocate(1); }
@@ -386,7 +432,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
__node->_M_next = __xnode->_M_next;
__node->_M_prev = __xnode->_M_prev;
__node->_M_next->_M_prev = __node->_M_prev->_M_next = __node;
- __xnode->_M_next = __xnode->_M_prev = __xnode;
+ _M_set_size(__x._M_get_size());
+ __x._M_init();
}
}
#endif
@@ -403,6 +450,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
{
this->_M_impl._M_node._M_next = &this->_M_impl._M_node;
this->_M_impl._M_node._M_prev = &this->_M_impl._M_node;
+ _M_set_size(0);
}
};
@@ -453,7 +501,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
* %empty.
*/
template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
- class list : protected _List_base<_Tp, _Alloc>
+ class _GLIBCXX_DEFAULT_ABI_TAG list : protected _List_base<_Tp, _Alloc>
{
// concept requirements
typedef typename _Alloc::value_type _Alloc_value_type;
@@ -893,7 +941,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
/** Returns the number of elements in the %list. */
size_type
size() const _GLIBCXX_NOEXCEPT
- { return std::distance(begin(), end()); }
+ { return this->_M_node_count(); }
/** Returns the size() of the largest possible %list. */
size_type
@@ -1295,6 +1343,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
__detail::_List_node_base::swap(this->_M_impl._M_node,
__x._M_impl._M_node);
+ size_t __xsize = __x._M_get_size();
+ __x._M_set_size(this->_M_get_size());
+ this->_M_set_size(__xsize);
+
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 431. Swapping containers with unequal allocators.
std::__alloc_swap<typename _Base::_Node_alloc_type>::
@@ -1339,6 +1391,9 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
this->_M_transfer(__position._M_const_cast(),
__x.begin(), __x.end());
+
+ this->_M_inc_size(__x._M_get_size());
+ __x._M_set_size(0);
}
}
@@ -1385,6 +1440,9 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
this->_M_transfer(__position._M_const_cast(),
__i._M_const_cast(), __j);
+
+ this->_M_inc_size(1);
+ __x._M_dec_size(1);
}
#if __cplusplus >= 201103L
@@ -1443,6 +1501,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
if (this != &__x)
_M_check_equal_allocators(__x);
+ size_t __n = this->_M_distance(__first._M_node, __last._M_node);
+ this->_M_inc_size(__n);
+ __x._M_dec_size(__n);
+
this->_M_transfer(__position._M_const_cast(),
__first._M_const_cast(),
__last._M_const_cast());
@@ -1688,6 +1750,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
{
_Node* __tmp = _M_create_node(__x);
__tmp->_M_hook(__position._M_node);
+ this->_M_inc_size(1);
}
#else
template<typename... _Args>
@@ -1696,6 +1759,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
{
_Node* __tmp = _M_create_node(std::forward<_Args>(__args)...);
__tmp->_M_hook(__position._M_node);
+ this->_M_inc_size(1);
}
#endif
@@ -1703,6 +1767,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
void
_M_erase(iterator __position) _GLIBCXX_NOEXCEPT
{
+ this->_M_dec_size(1);
__position._M_node->_M_unhook();
_Node* __n = static_cast<_Node*>(__position._M_node);
#if __cplusplus >= 201103L
@@ -18,7 +18,7 @@
// <http://www.gnu.org/licenses/>.
// { dg-do compile }
-// { dg-error "no matching" "" { target *-*-* } 1665 }
+// { dg-error "no matching" "" { target *-*-* } 1727 }
#include <list>
@@ -18,7 +18,7 @@
// <http://www.gnu.org/licenses/>.
// { dg-do compile }
-// { dg-error "no matching" "" { target *-*-* } 1617 }
+// { dg-error "no matching" "" { target *-*-* } 1679 }
#include <list>
@@ -18,7 +18,7 @@
// <http://www.gnu.org/licenses/>.
// { dg-do compile }
-// { dg-error "no matching" "" { target *-*-* } 1617 }
+// { dg-error "no matching" "" { target *-*-* } 1679 }
#include <list>
#include <utility>
@@ -18,7 +18,7 @@
// <http://www.gnu.org/licenses/>.
// { dg-do compile }
-// { dg-error "no matching" "" { target *-*-* } 1617 }
+// { dg-error "no matching" "" { target *-*-* } 1679 }
#include <list>
@@ -25,4 +25,4 @@
#include <vector>
-// { dg-error "multiple inlined namespaces" "" { target *-*-* } 279 }
+// { dg-error "multiple inlined namespaces" "" { target *-*-* } 290 }
This is the patch I intend to commit to make std::list::size() O(1) as required by C++11. This is an ABI change, so std::list will get tagged with abi_tag("cxx11") so that it mangles differently. I took a different approach to the way O(1) size() was implemented (and then reverted) for GCC 4.7.0, because I didn't like updating the size when node are (de)allocated. Instead this patch adjusts the size when nodes are added or removed from the list, rather then when they're allocated. Instead of littering the code with #if checks I added new _M_xxx_size() members that can be called unconditionally when modifying the list, but they do nothing when there's no size member. This means there's only a single #if condition added to std::list by this patch. There will be another patch coming soon to add C++11 allocator support to std::list, and another to add a non-COW std::string using abi_tag. I don't yet know what we should do about the --enable-symvers=gnu-versioned-namespace configuration, maybe we should move the soname for that option to libstdc++.so.8 and have _GLIBCXX_USE_CXX11_ABI=1 and _GLIBCXX_DEFAULT_ABI_TAG= set always, so that the versioned-namespace configuration always gets the new ABI and doesn't need to use the tag (because using that configuration already implies you're not interested in ABI compatibility). I'd prefer not to have versioned-namespace-with-new-abi and versioned-namespace-without-new-abi configurations, given that we don't know if anyone's even using versioned namespaces for anything serious. Tested x86_64-linux, with --disable-libstdcxx-cxx11-abi and without.