tmp/tmpdvfft_a3/{from.md → to.md}
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#### Sizeof <a id="expr.sizeof">[[expr.sizeof]]</a>
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The `sizeof` operator yields the number of bytes occupied by a
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non-potentially-overlapping object of the type of its operand. The
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operand is either an expression, which is an unevaluated operand
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[[
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not be applied to an expression that has function or
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the parenthesized name of such types, or to a
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bit-field. The result of `sizeof` applied to
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types is `1`. The result of `sizeof` applied
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type [[basic.fundamental]] is
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[*Note 1*:
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`sizeof(char32_t)`, and `sizeof(wchar_t)` are
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implementation-defined.[^21]
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[*Note 2*: See [[intro.memory]] for the definition of byte and
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[[
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representation. — *end note*]
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When applied to a reference type, the result is the size of the
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referenced type. When applied to a class, the result is the number of
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bytes in an object of that class including any padding required for
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placing objects of that type in an array. The result of applying
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`sizeof` to a potentially-overlapping subobject is the size of the type,
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not the size of the subobject.
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The lvalue-to-rvalue [[conv.lval]], array-to-pointer [[conv.array]], and
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function-to-pointer [[conv.func]] standard conversions are not applied
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to the operand of `sizeof`. If the operand is a prvalue, the temporary
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materialization conversion [[conv.rval]] is applied.
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@@ -51,7 +58,7 @@ struct count {
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The result of `sizeof` and `sizeof...` is a prvalue of type
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`std::size_t`.
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[*Note 3*: A `sizeof` expression is an integral constant expression
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[[expr.const]]. The type `std::size_t` is defined in the standard header
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`<cstddef>`
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#### Sizeof <a id="expr.sizeof">[[expr.sizeof]]</a>
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The `sizeof` operator yields the number of bytes occupied by a
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non-potentially-overlapping object of the type of its operand. The
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operand is either an expression, which is an unevaluated operand
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[[term.unevaluated.operand]], or a parenthesized *type-id*. The `sizeof`
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operator shall not be applied to an expression that has function or
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incomplete type, to the parenthesized name of such types, or to a
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glvalue that designates a bit-field. The result of `sizeof` applied to
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any of the narrow character types is `1`. The result of `sizeof` applied
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to any other fundamental type [[basic.fundamental]] is
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*implementation-defined*.
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[*Note 1*:
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In particular, the values of `sizeof(bool)`, `sizeof(char16_t)`,
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`sizeof(char32_t)`, and `sizeof(wchar_t)` are
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implementation-defined.[^21]
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— *end note*]
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[*Note 2*: See [[intro.memory]] for the definition of byte and
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[[term.object.representation]] for the definition of object
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representation. — *end note*]
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When applied to a reference type, the result is the size of the
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referenced type. When applied to a class, the result is the number of
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bytes in an object of that class including any padding required for
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placing objects of that type in an array. The result of applying
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`sizeof` to a potentially-overlapping subobject is the size of the type,
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not the size of the subobject.[^22]
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When applied to an array, the result is the total number of bytes in the
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array. This implies that the size of an array of n elements is n times
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the size of an element.
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The lvalue-to-rvalue [[conv.lval]], array-to-pointer [[conv.array]], and
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function-to-pointer [[conv.func]] standard conversions are not applied
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to the operand of `sizeof`. If the operand is a prvalue, the temporary
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materialization conversion [[conv.rval]] is applied.
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The result of `sizeof` and `sizeof...` is a prvalue of type
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`std::size_t`.
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[*Note 3*: A `sizeof` expression is an integral constant expression
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[[expr.const]]. The type `std::size_t` is defined in the standard header
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`<cstddef>` [[cstddef.syn]], [[support.types.layout]]. — *end note*]
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