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1260.is_constructible<int*,void*> reports true

Section: 21.3.6.4[meta.unary.prop]Status:ResolvedSubmitter: Peter DimovOpened: 2009-11-07Last modified: 2016-01-28

Priority:Not Prioritized

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Discussion:

The specification ofis_constructible<T,Args...> inN3000uses

static_cast<T>(create<Args>()...)

for the one-argument case, butstatic_cast also permitsunwanted conversions such asvoid* toT* andBase* toDerived*.

[Post-Rapperswil:]

Moved toNAD EditorialResolved, this issue is addressed by papern3047

Proposed resolution:

Change 21.3.6.4[meta.unary.prop], p6:

the predicate condition for a template specializationis_constructible<T, Args> shall be satisfied, if and onlyif the followingexpressionCEvariabledefinition would be well-formed:

• ifsizeof...(Args) ==01, the expression:

  static_cast<T>(create<Args>()...)T t;

• otherwisethe expression:

  T t(create<Args>()...);