установить параметры выделения памяти (set memory allocation parameters)
Ошибки (баги) (Bugs)
Specifying an invalid value for param does not generate an error.
A calculation error within the glibc implementation means that a
call of the form:
mallopt(M_MXFAST, n)
does not result in fastbins being employed for all allocations of
size up to n. To ensure desired results, n should be rounded up
to the next multiple greater than or equal to
(2k+1)*sizeof(size_t), where k is an integer.
If mallopt() is used to set M_PERTURB, then, as expected, the
bytes of allocated memory are initialized to the complement of
the byte in value, and when that memory is freed, the bytes of
the region are initialized to the byte specified in value.
However, there is an off-by-sizeof(size_t) error in the
implementation: instead of initializing precisely the block of
memory being freed by the call free(p), the block starting at
p+sizeof(size_t) is initialized.
