Microsoft-specific. When you declare a pointer with the __unaligned modifier, the compiler assumes that the pointer addresses data that is not aligned. Consequently, platform-appropriate code is generated to handle unaligned reads and writes through the pointer.

This modifier describes the alignment of the data addressed by the pointer; the pointer itself is assumed to be aligned.

The necessity for the __unaligned keyword varies by platform and environment. Failure to mark data appropriately can result in issues ranging from performance penalties to hardware faults. The __unaligned modifier is not valid for the x86 platform.

For compatibility with previous versions, _unaligned is a synonym for __unaligned unless compiler option /Za (Disable language extensions) is specified.

For more information about alignment, see:

• align

• alignof Operator

• pack

• /Zp (Struct Member Alignment)

• Examples of Structure Alignment

Keywords