Allocates memory on a specified alignment boundary.


void * _aligned_offset_malloc(
   size_t size,
   size_t alignment,
   size_t offset


The size of the requested memory allocation.

The alignment value, which must be an integer power of 2.

The offset into the memory allocation to force the alignment.

Return value

A pointer to the memory block that was allocated or NULL if the operation failed.


_aligned_offset_malloc is useful in situations where alignment is needed on a nested element; for example, if alignment was needed on a nested class.

_aligned_offset_malloc is based on malloc; for more information, see malloc.

_aligned_offset_malloc is marked __declspec(noalias) and __declspec(restrict), meaning that the function is guaranteed not to modify global variables and that the pointer returned isn't aliased. For more information, see noalias and restrict.

This function sets errno to ENOMEM if the memory allocation failed or if the requested size was greater than _HEAP_MAXREQ. For more information about errno, see errno, _doserrno, _sys_errlist, and _sys_nerr. Also, _aligned_offset_malloc validates its parameters. If alignment isn't a power of 2, or if offset is non-zero and greater than or equal to size, this function invokes the invalid parameter handler, as described in Parameter validation. If execution is allowed to continue, this function returns NULL and sets errno to EINVAL.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.


Routine Required header
_aligned_offset_malloc <malloc.h>


For more information, see _aligned_malloc.

See also

Data alignment