Why do I need std::get_temporary_buffer?

Question

For what purpose I should use std::get_temporary_buffer? Standard says the following:

Obtains a pointer to storage sufficient to store up to n adjacen

Answer 1

ptrdiff_t            request = 12
pair p       = get_temporary_buffer(request);
int*                 base    = p.first;
ptrdiff_t            respond = p.sencond;
assert( is_valid( base, base + respond ) );

respond may be less than request.

size_t require = 12;
int*   base    = static_cast( ::operator new( require*sizeof(int) ) );
assert( is_valid( base, base + require ) );

the actual size of base must greater or equal to require.