On 13-03-16 10:40 PM, Jason Merrill wrote:
On 03/16/2013 03:28 PM, Jason Merrill wrote:
I have no idea why the existing code tried to deduce the desired quals
from current_class_ref rather than just look at the object it has.
Well, maybe now I do; when I tested all my changes again before checking
in, this one caused a crash because I had left out another change that
it depends on. Previously we gave the 'this' capture in a lambda a
DECLTYPE_TYPE type since the enclosing class is a dependent type, but
that means that *this has no type at all and so we can't look at its
quals. But that isn't necessary; we know enough about the type of
'this' that it's a pointer to some instantiation of this class template,
so we can give the capture field and proxy that type rather than mess
with DECLTYPE_TYPE. We could limit this change to only POINTER_TYPE,
but we might as well save a bit of memory and only use the DECLTYPE_TYPE
when we really don't know anything about the type being captured;
specifically, when we don't know whether or not it's a reference.
Tested x86_64-pc-linux-gnu, applying to trunk.
Hi Jason,
It seems this change introduced the following segfault building
compatibility-thread-c++0x.cc for an arm eabi target.
ice.ii:48:20: internal compiler error: Segmentation fault
(__args) ...);
^
0xa7b67f crash_signal
../../gcc/toplev.c:332
0x4e98e2 resolve_args
../../gcc/cp/call.c:3739
0x5022d7 build_new_function_call(tree_node*, vec<tree_node*, va_gc,
vl_embed>**, bool, int)
../../gcc/cp/call.c:3849
0x66dc42 finish_call_expr(tree_node*, vec<tree_node*, va_gc,
vl_embed>**, bool, bool, int)
../../gcc/cp/semantics.c:2214
Attached is a reduced testcase. Sorry, for reporting it on gcc-patches
but bugzilla is currently offline.
Regards,
Ryan Mansfield
namespace std __attribute__ ((__visibility__ ("default")))
{
template < typename _Tp > struct remove_reference
{
typedef _Tp type;
};
template < typename _Tp > constexpr _Tp
&& forward (typename std::remove_reference < _Tp >::type & __t) noexcept
{
return static_cast < _Tp && >(__t);
}
template < typename _Res, typename _T1,
typename _T2 >
struct _Reference_wrapper_base <_Res (_T1::*) (_T2) const volatile
>:binary_function < const volatile _T1 *, _T2, _Res >
{
};
template < typename _Tp > class reference_wrapper:public
_Reference_wrapper_base < typename remove_cv <
_Tp >::type >
{
};
template < typename _Tp > inline reference_wrapper < _Tp >
ref (_Tp & __t) noexcept
{
}
template < typename _Signature > struct _Bind_simple;
template < typename _Func, typename ... _BoundArgs > struct
_Bind_simple_helper
{
typedef _Bind_simple < __func_type (typename decay <
_BoundArgs >::type ...) > __type;
};
template < typename _Callable,
typename ... _Args > typename _Bind_simple_helper < _Callable,
_Args ... >::__type __bind_simple (_Callable && __callable, _Args
&& ... __args)
{
}
template < typename _Signature > class function;
struct once_flag
{
};
template < typename _Callable,
typename ... _Args > void call_once (once_flag & __once, _Callable
&& __f, _Args && ... __args)
{
auto __callable = std::__bind_simple (std::forward < _Callable > (__f),
std::forward < _Args >
(__args) ...);
__once_functor =[&]()
{
__callable ();
};
}
class _State_base
{
once_flag _M_once;
void _M_set_result (function < _Ptr_type () > __res,
bool __ignore_failure = false)
{
bool __set = __ignore_failure;
call_once (_M_once, &_State_base::_M_do_set, this, ref (__res),
ref (__set));
}
private:void _M_do_set (function < _Ptr_type () > &__f, bool & __set)
{
}
}
}
