Memory alignment-notes

The key is the following four concepts:

1. Alignment of the Data Type itself: Alignment of the basic data type. (Note: If a struct appears as a member, its alignment value can be found in Reference 3)

2. Specify the alignment value: # The alignment value specified for progma pack (value.

3. The alignment value of a struct or class: The value with the largest alignment value among its members.

4.True alignment of data members, struct, and classes = min (Self Alignment value, # value specified by progma pack)

In addition, the default # progma pack value for Linux is 4. Windows may consider that there is no default value.