[expr.new] - C++14 → C++17

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@@ -2,16 +2,18 @@
 The *new-expression* attempts to create an object of the *type-id* (
 [[dcl.name]]) or *new-type-id* to which it is applied. The type of that
 object is the *allocated type*. This type shall be a complete object
 type, but not an abstract class type or array thereof (
-[[intro.object]],  [[basic.types]],  [[class.abstract]]). It is
-*implementation-defined* whether over-aligned types are supported (
-[[basic.align]]). because references are not objects, references cannot
-be created by *new-expression*s. the *type-id* may be a cv-qualified
-type, in which case the object created by the *new-expression* has a
-cv-qualified type.
 ``` bnf
 new-expression:
     '::'ₒₚₜ 'new' new-placementₒₚₜ new-type-id new-initializerₒₚₜ
     '::'ₒₚₜ 'new' new-placementₒₚₜ '(' type-id ')' new-initializerₒₚₜ
@@ -44,50 +46,67 @@ new-initializer:
     '(' expression-listₒₚₜ ')'
     braced-init-list
 ```
 Entities created by a *new-expression* have dynamic storage duration (
-[[basic.stc.dynamic]]). the lifetime of such an entity is not
-necessarily restricted to the scope in which it is created. If the
-entity is a non-array object, the *new-expression* returns a pointer to
-the object created. If it is an array, the *new-expression* returns a
-pointer to the initial element of the array.
-If the `auto` appears in the of a or of a , the shall contain a of the
-form
-``` bnf
-'(' assignment-expression ')'
-```
-The allocated type is deduced from the as follows: Let `e` be the
-*assignment-expression* in the and `T` be the or of the , then the
-allocated type is the type deduced for the variable `x` in the invented
-declaration ([[dcl.spec.auto]]):
 ``` cpp
-T x(e);
 ```
 ``` cpp
 new auto(1);                    // allocated type is int
 auto x = new auto('a');         // allocated type is char, x is of type char*
 ```
 The *new-type-id* in a *new-expression* is the longest possible sequence
-of *new-declarator*s. this prevents ambiguities between the declarator
-operators `&`, `&&`, `*`, and `[]` and their expression counterparts.
 ``` cpp
 new int * i;                    // syntax error: parsed as (new int*) i, not as (new int)*i
 ```
 The `*` is the pointer declarator and not the multiplication operator.
-parentheses in a *new-type-id* of a *new-expression* can have surprising
 effects.
 ``` cpp
 new int(*[10])();               // error
 ```
 is ill-formed because the binding is
@@ -102,66 +121,85 @@ be used to create objects of compound types ([[basic.compound]]):
 ``` cpp
 new (int (*[10])());
 ```
 allocates an array of `10` pointers to functions (taking no argument and
-returning `int`.
 When the allocated object is an array (that is, the
 *noptr-new-declarator* syntax is used or the *new-type-id* or *type-id*
 denotes an array type), the *new-expression* yields a pointer to the
-initial element (if any) of the array. both `new int` and `new int[10]`
-have type `int*` and the type of `new int[i][10]` is `int (*)[10]` The
-*attribute-specifier-seq* in a *noptr-new-declarator* appertains to the
-associated array type.
 Every *constant-expression* in a *noptr-new-declarator* shall be a
 converted constant expression ([[expr.const]]) of type `std::size_t`
 and shall evaluate to a strictly positive value. The *expression* in a
-*noptr-new-declarator*is implicitly converted to `std::size_t`. given
-the definition `int n = 42`, `new float[n][5]` is well-formed (because
-`n` is the *expression* of a *noptr-new-declarator*), but
-`new float[5][n]` is ill-formed (because `n` is not a constant
-expression).
 The *expression* in a *noptr-new-declarator* is erroneous if:
 - the expression is of non-class type and its value before converting to
   `std::size_t` is less than zero;
 - the expression is of class type and its value before application of
   the second standard conversion ([[over.ics.user]])[^18] is less than
   zero;
 - its value is such that the size of the allocated object would exceed
-  the implementation-defined limit (annex  [[implimits]]); or
 - the *new-initializer* is a *braced-init-list* and the number of array
   elements for which initializers are provided (including the
   terminating `'\0'` in a string literal ([[lex.string]])) exceeds the
   number of elements to initialize.
-If the *expression*, after converting to `std::size_t`, is a core
-constant expression and the expression is erroneous, the program is
-ill-formed. Otherwise, a *new-expression* with an erroneous expression
-does not call an allocation function and terminates by throwing an
-exception of a type that would match a handler ([[except.handle]]) of
-type `std::bad_array_new_length` ([[new.badlength]]). When the value of
-the *expression* is zero, the allocation function is called to allocate
-an array with no elements.
 A *new-expression* may obtain storage for the object by calling an
-*allocation function* ([[basic.stc.dynamic.allocation]]). If the
 *new-expression* terminates by throwing an exception, it may release
 storage by calling a deallocation function (
 [[basic.stc.dynamic.deallocation]]). If the allocated type is a
 non-array type, the allocation function’s name is `operator new` and the
 deallocation function’s name is `operator delete`. If the allocated type
 is an array type, the allocation function’s name is `operator new[]` and
-the deallocation function’s name is `operator delete[]`. an
-implementation shall provide default definitions for the global
-allocation functions ([[basic.stc.dynamic]],  [[new.delete.single]],
-[[new.delete.array]]). A C++program can provide alternative definitions
-of these functions ([[replacement.functions]]) and/or class-specific
-versions ([[class.free]]).
 If the *new-expression* begins with a unary `::` operator, the
 allocation function’s name is looked up in the global scope. Otherwise,
 if the allocated type is a class type `T` or array thereof, the
 allocation function’s name is looked up in the scope of `T`. If this
@@ -187,10 +225,12 @@ true were the allocation not extended:
   *delete-expression*s, and
 - the evaluation of `e2` is sequenced before the evaluation of the
   *delete-expression* whose operand is the pointer value produced by
   `e1`.
 ``` cpp
   void mergeable(int x) {
     // These allocations are safe for merging:
     std::unique_ptr<char[]> a{new (std::nothrow) char[8]};
     std::unique_ptr<char[]> b{new (std::nothrow) char[8]};
@@ -209,110 +249,140 @@ void mergeable(int x) {
       throw;
     }
   }
 ```
 When a *new-expression* calls an allocation function and that allocation
 has not been extended, the *new-expression* passes the amount of space
 requested to the allocation function as the first argument of type
 `std::size_t`. That argument shall be no less than the size of the
 object being created; it may be greater than the size of the object
-being created only if the object is an array. For arrays of `char` and
-`unsigned char`, the difference between the result of the
-*new-expression* and the address returned by the allocation function
 shall be an integral multiple of the strictest fundamental alignment
 requirement ([[basic.align]]) of any object type whose size is no
-greater than the size of the array being created. Because allocation
-functions are assumed to return pointers to storage that is
-appropriately aligned for objects of any type with fundamental
-alignment, this constraint on array allocation overhead permits the
-common idiom of allocating character arrays into which objects of other
-types will later be placed.
 When a *new-expression* calls an allocation function and that allocation
 has been extended, the size argument to the allocation call shall be no
 greater than the sum of the sizes for the omitted calls as specified
 above, plus the size for the extended call had it not been extended,
 plus any padding necessary to align the allocated objects within the
 allocated memory.
 The *new-placement* syntax is used to supply additional arguments to an
-allocation function. If used, overload resolution is performed on a
-function call created by assembling an argument list consisting of the
-amount of space requested (the first argument) and the expressions in
-the *new-placement* part of the *new-expression* (the second and
-succeeding arguments). The first of these arguments has type
-`std::size_t` and the remaining arguments have the corresponding types
-of the expressions in the *new-placement*.
-- `new T` results in a call of `operator
-  new(sizeof(T))`,
-- `new(2,f) T` results in a call of `operator
-  new(sizeof(T),2,f)`,
-- `new T[5]` results in a call of `operator
-  new[](sizeof(T)*5+x)`, and
-- `new(2,f) T[5]` results in a call of `operator
-  new[](sizeof(T)*5+y,2,f)`.
-Here, `x` and `y` are non-negative unspecified values representing array
-allocation overhead; the result of the *new-expression* will be offset
-by this amount from the value returned by `operator new[]`. This
-overhead may be applied in all array *new-expression*s, including those
-referencing the library function `operator new[](std::size_t, void*)`
-and other placement allocation functions. The amount of overhead may
-vary from one invocation of `new` to another.
-unless an allocation function is declared with a non-throwing
-*exception-specification* ([[except.spec]]), it indicates failure to
-allocate storage by throwing a `std::bad_alloc` exception (Clause
-[[except]],  [[bad.alloc]]); it returns a non-null pointer otherwise. If
-the allocation function is declared with a non-throwing
-*exception-specification*, it returns null to indicate failure to
-allocate storage and a non-null pointer otherwise. If the allocation
-function returns null, initialization shall not be done, the
-deallocation function shall not be called, and the value of the
-*new-expression* shall be null.
-when the allocation function returns a value other than null, it must be
-a pointer to a block of storage in which space for the object has been
-reserved. The block of storage is assumed to be appropriately aligned
-and of the requested size. The address of the created object will not
-necessarily be the same as that of the block if the object is an array.
 A *new-expression* that creates an object of type `T` initializes that
 object as follows:
 - If the *new-initializer* is omitted, the object is
-  default-initialized ([[dcl.init]]). If no initialization is
-  performed, the object has an indeterminate value.
 - Otherwise, the *new-initializer* is interpreted according to the
   initialization rules of  [[dcl.init]] for direct-initialization.
-The invocation of the allocation function is indeterminately sequenced
-with respect to the evaluations of expressions in the *new-initializer*.
-Initialization of the allocated object is sequenced before the value
-computation of the *new-expression*. It is unspecified whether
-expressions in the *new-initializer* are evaluated if the allocation
-function returns the null pointer or exits using an exception.
 If the *new-expression* creates an object or an array of objects of
 class type, access and ambiguity control are done for the allocation
 function, the deallocation function ([[class.free]]), and the
 constructor ([[class.ctor]]). If the *new-expression* creates an array
 of objects of class type, the destructor is potentially invoked (
 [[class.dtor]]).
 If any part of the object initialization described above[^19] terminates
-by throwing an exception, storage has been obtained for the object, and
-a suitable deallocation function can be found, the deallocation function
-is called to free the memory in which the object was being constructed,
-after which the exception continues to propagate in the context of the
-*new-expression*. If no unambiguous matching deallocation function can
-be found, propagating the exception does not cause the object’s memory
-to be freed. This is appropriate when the called allocation function
 does not allocate memory; otherwise, it is likely to result in a memory
-leak.
 If the *new-expression* begins with a unary `::` operator, the
 deallocation function’s name is looked up in the global scope.
 Otherwise, if the allocated type is a class type `T` or an array
 thereof, the deallocation function’s name is looked up in the scope of
@@ -324,17 +394,19 @@ A declaration of a placement deallocation function matches the
 declaration of a placement allocation function if it has the same number
 of parameters and, after parameter transformations ([[dcl.fct]]), all
 parameter types except the first are identical. If the lookup finds a
 single matching deallocation function, that function will be called;
 otherwise, no deallocation function will be called. If the lookup finds
-the two-parameter form of a usual deallocation function (
 [[basic.stc.dynamic.deallocation]]) and that function, considered as a
 placement deallocation function, would have been selected as a match for
 the allocation function, the program is ill-formed. For a non-placement
 allocation function, the normal deallocation function lookup is used to
 find the matching deallocation function ([[expr.delete]])
 ``` cpp
 struct S {
   // Placement allocation function:
   static void* operator new(std::size_t, std::size_t);
@@ -344,10 +416,12 @@ struct S {
 S* p = new (0) S;   // ill-formed: non-placement deallocation function matches
                     // placement allocation function
 ```
 If a *new-expression* calls a deallocation function, it passes the value
 returned from the allocation function call as the first argument of type
 `void*`. If a placement deallocation function is called, it is passed
 the same additional arguments as were passed to the placement allocation
 function, that is, the same arguments as those specified with the

 The *new-expression* attempts to create an object of the *type-id* (
 [[dcl.name]]) or *new-type-id* to which it is applied. The type of that
 object is the *allocated type*. This type shall be a complete object
 type, but not an abstract class type or array thereof (
+[[intro.object]],  [[basic.types]],  [[class.abstract]]).
+[*Note 1*: Because references are not objects, references cannot be
+created by *new-expression*s. — *end note*]
+[*Note 2*: The *type-id* may be a cv-qualified type, in which case the
+object created by the *new-expression* has a cv-qualified
+type. — *end note*]
 ``` bnf
 new-expression:
     '::'ₒₚₜ 'new' new-placementₒₚₜ new-type-id new-initializerₒₚₜ
     '::'ₒₚₜ 'new' new-placementₒₚₜ '(' type-id ')' new-initializerₒₚₜ
     '(' expression-listₒₚₜ ')'
     braced-init-list
 ```
 Entities created by a *new-expression* have dynamic storage duration (
+[[basic.stc.dynamic]]).
+[*Note 3*:  The lifetime of such an entity is not necessarily
+restricted to the scope in which it is created. — *end note*]
+If the entity is a non-array object, the *new-expression* returns a
+pointer to the object created. If it is an array, the *new-expression*
+returns a pointer to the initial element of the array.
+If a placeholder type ([[dcl.spec.auto]]) appears in the
+*type-specifier-seq* of a *new-type-id* or *type-id* of a
+*new-expression*, the allocated type is deduced as follows: Let *init*
+be the *new-initializer*, if any, and `T` be the *new-type-id* or
+*type-id* of the *new-expression*, then the allocated type is the type
+deduced for the variable `x` in the invented declaration (
+[[dcl.spec.auto]]):
 ``` cpp
+T x init ;
 ```
+[*Example 1*:
 ``` cpp
 new auto(1);                    // allocated type is int
 auto x = new auto('a');         // allocated type is char, x is of type char*
+template<class T> struct A { A(T, T); };
+auto y = new A{1, 2};           // allocated type is A<int>
 ```
+— *end example*]
 The *new-type-id* in a *new-expression* is the longest possible sequence
+of *new-declarator*s.
+[*Note 4*: This prevents ambiguities between the declarator operators
+`&`, `&&`, `*`, and `[]` and their expression
+counterparts. — *end note*]
+[*Example 2*:
 ``` cpp
 new int * i;                    // syntax error: parsed as (new int*) i, not as (new int)*i
 ```
 The `*` is the pointer declarator and not the multiplication operator.
+— *end example*]
+[*Note 5*:
+Parentheses in a *new-type-id* of a *new-expression* can have surprising
 effects.
+[*Example 3*:
 ``` cpp
 new int(*[10])();               // error
 ```
 is ill-formed because the binding is
 ``` cpp
 new (int (*[10])());
 ```
 allocates an array of `10` pointers to functions (taking no argument and
+returning `int`).
+— *end example*]
+— *end note*]
 When the allocated object is an array (that is, the
 *noptr-new-declarator* syntax is used or the *new-type-id* or *type-id*
 denotes an array type), the *new-expression* yields a pointer to the
+initial element (if any) of the array.
+[*Note 6*: Both `new int` and `new int[10]` have type `int*` and the
+type of `new int[i][10]` is `int (*)[10]` — *end note*]
+The *attribute-specifier-seq* in a *noptr-new-declarator* appertains to
+the associated array type.
 Every *constant-expression* in a *noptr-new-declarator* shall be a
 converted constant expression ([[expr.const]]) of type `std::size_t`
 and shall evaluate to a strictly positive value. The *expression* in a
+*noptr-new-declarator* is implicitly converted to `std::size_t`.
+[*Example 4*: Given the definition `int n = 42`, `new float[n][5]` is
+well-formed (because `n` is the *expression* of a
+*noptr-new-declarator*), but `new float[5][n]` is ill-formed (because
+`n` is not a constant expression). — *end example*]
 The *expression* in a *noptr-new-declarator* is erroneous if:
 - the expression is of non-class type and its value before converting to
   `std::size_t` is less than zero;
 - the expression is of class type and its value before application of
   the second standard conversion ([[over.ics.user]])[^18] is less than
   zero;
 - its value is such that the size of the allocated object would exceed
+  the *implementation-defined* limit (Annex  [[implimits]]); or
 - the *new-initializer* is a *braced-init-list* and the number of array
   elements for which initializers are provided (including the
   terminating `'\0'` in a string literal ([[lex.string]])) exceeds the
   number of elements to initialize.
+If the *expression* is erroneous after converting to `std::size_t`:
+- if the *expression* is a core constant expression, the program is
+  ill-formed;
+- otherwise, an allocation function is not called; instead
+  - if the allocation function that would have been called has a
+    non-throwing exception specification ([[except.spec]]), the value
+    of the *new-expression* is the null pointer value of the required
+    result type;
+  - otherwise, the *new-expression* terminates by throwing an exception
+    of a type that would match a handler ([[except.handle]]) of type
+    `std::bad_array_new_length` ([[new.badlength]]).
+When the value of the *expression* is zero, the allocation function is
+called to allocate an array with no elements.
 A *new-expression* may obtain storage for the object by calling an
+allocation function ([[basic.stc.dynamic.allocation]]). If the
 *new-expression* terminates by throwing an exception, it may release
 storage by calling a deallocation function (
 [[basic.stc.dynamic.deallocation]]). If the allocated type is a
 non-array type, the allocation function’s name is `operator new` and the
 deallocation function’s name is `operator delete`. If the allocated type
 is an array type, the allocation function’s name is `operator new[]` and
+the deallocation function’s name is `operator delete[]`.
+[*Note 7*: An implementation shall provide default definitions for the
+global allocation functions ([[basic.stc.dynamic]],
+[[new.delete.single]],  [[new.delete.array]]). A C++program can provide
+alternative definitions of these functions ([[replacement.functions]])
+and/or class-specific versions ([[class.free]]). The set of allocation
+and deallocation functions that may be called by a *new-expression* may
+include functions that do not perform allocation or deallocation; for
+example, see [[new.delete.placement]]. — *end note*]
 If the *new-expression* begins with a unary `::` operator, the
 allocation function’s name is looked up in the global scope. Otherwise,
 if the allocated type is a class type `T` or array thereof, the
 allocation function’s name is looked up in the scope of `T`. If this
   *delete-expression*s, and
 - the evaluation of `e2` is sequenced before the evaluation of the
   *delete-expression* whose operand is the pointer value produced by
   `e1`.
+[*Example 5*:
 ``` cpp
   void mergeable(int x) {
     // These allocations are safe for merging:
     std::unique_ptr<char[]> a{new (std::nothrow) char[8]};
     std::unique_ptr<char[]> b{new (std::nothrow) char[8]};
       throw;
     }
   }
 ```
+— *end example*]
 When a *new-expression* calls an allocation function and that allocation
 has not been extended, the *new-expression* passes the amount of space
 requested to the allocation function as the first argument of type
 `std::size_t`. That argument shall be no less than the size of the
 object being created; it may be greater than the size of the object
+being created only if the object is an array. For arrays of `char`,
+`unsigned char`, and `std::byte`, the difference between the result of
+the *new-expression* and the address returned by the allocation function
 shall be an integral multiple of the strictest fundamental alignment
 requirement ([[basic.align]]) of any object type whose size is no
+greater than the size of the array being created.
+[*Note 8*:  Because allocation functions are assumed to return pointers
+to storage that is appropriately aligned for objects of any type with
+fundamental alignment, this constraint on array allocation overhead
+permits the common idiom of allocating character arrays into which
+objects of other types will later be placed. — *end note*]
 When a *new-expression* calls an allocation function and that allocation
 has been extended, the size argument to the allocation call shall be no
 greater than the sum of the sizes for the omitted calls as specified
 above, plus the size for the extended call had it not been extended,
 plus any padding necessary to align the allocated objects within the
 allocated memory.
 The *new-placement* syntax is used to supply additional arguments to an
+allocation function; such an expression is called a *placement
+*new-expression**.
+Overload resolution is performed on a function call created by
+assembling an argument list. The first argument is the amount of space
+requested, and has type `std::size_t`. If the type of the allocated
+object has new-extended alignment, the next argument is the type’s
+alignment, and has type `std::align_val_t`. If the *new-placement*
+syntax is used, the *initializer-clause*s in its *expression-list* are
+the succeeding arguments. If no matching function is found and the
+allocated object type has new-extended alignment, the alignment argument
+is removed from the argument list, and overload resolution is performed
+again.
+[*Example 6*:
+- `new T` results in one of the following calls:
+ ``` cpp
+  operator new(sizeof(T))
+ operator new(sizeof(T), std::align_val_t(alignof(T)))
+  ```
+- `new(2,f) T` results in one of the following calls:
+  ``` cpp
+  operator new(sizeof(T), 2, f)
+  operator new(sizeof(T), std::align_val_t(alignof(T)), 2, f)
+  ```
+- `new T[5]` results in one of the following calls:
+ ``` cpp
+  operator new[](sizeof(T) * 5 + x)
+  operator new[](sizeof(T) * 5 + x, std::align_val_t(alignof(T)))
+  ```
+- `new(2,f) T[5]` results in one of the following calls:
+  ``` cpp
+  operator new[](sizeof(T) * 5 + x, 2, f)
+  operator new[](sizeof(T) * 5 + x, std::align_val_t(alignof(T)), 2, f)
+  ```
+Here, each instance of `x` is a non-negative unspecified value
+representing array allocation overhead; the result of the
+*new-expression* will be offset by this amount from the value returned
+by `operator new[]`. This overhead may be applied in all array
+*new-expression*s, including those referencing the library function
+`operator new[](std::size_t, void*)` and other placement allocation
+functions. The amount of overhead may vary from one invocation of `new`
+to another.
+— *end example*]
+[*Note 9*: Unless an allocation function has a non-throwing exception
+specification ([[except.spec]]), it indicates failure to allocate
+storage by throwing a `std::bad_alloc` exception (
+[[basic.stc.dynamic.allocation]], Clause  [[except]],  [[bad.alloc]]);
+it returns a non-null pointer otherwise. If the allocation function has
+a non-throwing exception specification, it returns null to indicate
+failure to allocate storage and a non-null pointer
+otherwise. — *end note*]
+If the allocation function is a non-allocating form (
+[[new.delete.placement]]) that returns null, the behavior is undefined.
+Otherwise, if the allocation function returns null, initialization shall
+not be done, the deallocation function shall not be called, and the
+value of the *new-expression* shall be null.
+[*Note 10*: When the allocation function returns a value other than
+null, it must be a pointer to a block of storage in which space for the
+object has been reserved. The block of storage is assumed to be
+appropriately aligned and of the requested size. The address of the
+created object will not necessarily be the same as that of the block if
+the object is an array. — *end note*]
 A *new-expression* that creates an object of type `T` initializes that
 object as follows:
 - If the *new-initializer* is omitted, the object is
+  default-initialized ([[dcl.init]]). \[*Note 11*: If no initialization
+ is performed, the object has an indeterminate value. — *end note*]
 - Otherwise, the *new-initializer* is interpreted according to the
   initialization rules of  [[dcl.init]] for direct-initialization.
+The invocation of the allocation function is sequenced before the
+evaluations of expressions in the *new-initializer*. Initialization of
+the allocated object is sequenced before the value computation of the
+*new-expression*.
 If the *new-expression* creates an object or an array of objects of
 class type, access and ambiguity control are done for the allocation
 function, the deallocation function ([[class.free]]), and the
 constructor ([[class.ctor]]). If the *new-expression* creates an array
 of objects of class type, the destructor is potentially invoked (
 [[class.dtor]]).
 If any part of the object initialization described above[^19] terminates
+by throwing an exception and a suitable deallocation function can be
+found, the deallocation function is called to free the memory in which
+the object was being constructed, after which the exception continues to
+propagate in the context of the *new-expression*. If no unambiguous
+matching deallocation function can be found, propagating the exception
+does not cause the object’s memory to be freed.
+[*Note 12*: This is appropriate when the called allocation function
 does not allocate memory; otherwise, it is likely to result in a memory
+leak. — *end note*]
 If the *new-expression* begins with a unary `::` operator, the
 deallocation function’s name is looked up in the global scope.
 Otherwise, if the allocated type is a class type `T` or an array
 thereof, the deallocation function’s name is looked up in the scope of
 declaration of a placement allocation function if it has the same number
 of parameters and, after parameter transformations ([[dcl.fct]]), all
 parameter types except the first are identical. If the lookup finds a
 single matching deallocation function, that function will be called;
 otherwise, no deallocation function will be called. If the lookup finds
+a usual deallocation function with a parameter of type `std::size_t` (
 [[basic.stc.dynamic.deallocation]]) and that function, considered as a
 placement deallocation function, would have been selected as a match for
 the allocation function, the program is ill-formed. For a non-placement
 allocation function, the normal deallocation function lookup is used to
 find the matching deallocation function ([[expr.delete]])
+[*Example 7*:
 ``` cpp
 struct S {
   // Placement allocation function:
   static void* operator new(std::size_t, std::size_t);
 S* p = new (0) S;   // ill-formed: non-placement deallocation function matches
                     // placement allocation function
 ```
+— *end example*]
 If a *new-expression* calls a deallocation function, it passes the value
 returned from the allocation function call as the first argument of type
 `void*`. If a placement deallocation function is called, it is passed
 the same additional arguments as were passed to the placement allocation
 function, that is, the same arguments as those specified with the

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