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Suggestion here is that lock API of weak_ptr and shared_ptr ctor which
takes weak_ptr as argument should atomically call reset on weak_ptr when
they fail to create a shared_ptr out of weak_ptr

This  has below advantage

1) It will automatically reduce the weak count of control block when its
not possible to create a shared_ptr from weak_ptr
2) User is not required to remember to call reset on weak_ptr which might
have static storage and unless reset explicitly will never reduce the weak
count and as we know unless weak_count is zero the control block and for
make_shared version the object can not be deleted

The reset need to be done atomically in above API's so no other thread can
assign weak_ptr in-between to different control block.

Thanks


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<div dir=3D"ltr">Suggestion here is that lock API of weak_ptr and shared_pt=
r ctor which takes weak_ptr as argument should atomically call reset on wea=
k_ptr when they fail to create a shared_ptr out of weak_ptr<div><br></div><=
div>This =C2=A0has below advantage</div><div><br></div><div>1) It will auto=
matically reduce the weak count of control block when its not possible to c=
reate a shared_ptr from weak_ptr</div><div>2) User is not required to remem=
ber to call reset on weak_ptr which might have static storage and unless re=
set explicitly will never reduce the weak count and as we know unless weak_=
count is zero the control block and for make_shared version the object can =
not be deleted</div><div><br></div><div>The reset need to be done atomicall=
y in above API&#39;s so no other thread can assign weak_ptr in-between to d=
ifferent control block.</div><div><br></div><div>Thanks</div><div><br></div=
><div><br></div></div>

<p></p>

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