#PB_Structure_AlignC

[PureGuy]

I just noticed the internal ACE_HEADER structure is to small in x64.
So I thought simply use #PB_Structure_AlignC, but it doesn't make a difference.

Shouldn't the #PB_Structure_AlignC make sure that the structure is a multiple of 8 on x64?

Code: Select all

Structure ACE_HEADER_ Align #PB_Structure_AlignC
  AceType.b
  AceFlags.b
  AceSize.w
EndStructure

Debug SizeOf(ACE_HEADER_)

[Josh]

Shouldn't the #PB_Structure_AlignC make sure that the structure is a multiple of 8 on x64?

No, that's a little bit complexer. There was a comprehensive thread about #PB_Structure_AlignC, but I'm afraid, this thread is moved into the hidden forum for solved Bug-Reports. As far as I know, there are following terms:

- Each item is aligned to a multiple value of its own size
- Stucture unions are aligned to a multiple value of its largest item
- The structure is padded to a multiple value of its largest item

This conditions are the same for 32 and 64 bit. I often use #PB_Structure_AlignC and since some BP-Versions I couldn't locate any problems.

P.S.: If you are not sure, that there is a bug, please use the forum for questions and not the bug-forum.

[PureGuy]

P.S.: If you are not sure, that there is a bug, please use the forum for questions and not the bug-forum.

Actually I'm sure there is at least 1 bug, cause the structure is to small.
According to the help file, there is a second bug, cause #PB_Structure_AlignC doesn't here align like C.

[DontTalkToMe]

Shouldn't the #PB_Structure_AlignC make sure that the structure is a multiple of 8 on x64?

No, why ?

According to the help file, there is a second bug, cause #PB_Structure_AlignC doesn't here align like C.

How did you test this ?

If SizeOf(ACE_HEADER_) is 4 should be ok afaik.

1 + 1 + 2, largest alignment is to 2, structure size must be a multiple of 2.

Code: Select all

	struct MyStruct
	{
		char a;
		char b;	
		short c;
	};

	cout << "sizeof(MyStruct) = " << sizeof(MyStruct) << endl;

Prints 4 on Visual C++ x64.

[Fred]

In C, it align to largest member size, not to 8.