Collapse the table of content
Expand the table of content
Important This document may not represent best practices for current development, links to downloads and other resources may no longer be valid. Current recommended version can be found here. ArchiveDisclaimer


Allocates memory on a specified alignment boundary.

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


[in] size

The size of the requested memory allocation.

[in] alignment

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

[in] offset

The offset into the memory allocation to force the alignment.

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 is not aliased. For more information, see noalias and restrict.

In Visual C++ 2005, 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 is not a power of 2 or if offset is greater than or equal to size and nonzero, 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.

Routine Required header Compatibility



Windows 95, Windows 98, Windows 98 Second Edition, Windows Millennium Edition, Windows NT 4.0, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003

For more information, see _aligned_malloc.

© 2016 Microsoft