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Posted: **Fri May 17, 2024 11:14 am**

PB6.11 b2
Why sizeof returns 0?, should't be the pointer size?
With this behaviour is not possible to do this:

Structure MYSTRUCT
	*arr.RECT[0]
EndStructure

Define.MYSTRUCT *st

Debug SizeOf(MYSTRUCT) ;0 ??
*st =  AllocateMemory(SizeOf(MYSTRUCT)) ;ERROR

;Not possible
*st\arr = AllocateMemory(SizeOf(RECT) * 4)
*st\arr[2]\left = 10

Could this be changed for the next version?

Posted: **Fri May 17, 2024 11:20 am**

The static array with *arr.RECT[0] has no elements (not even index 0). It is no pointer to an array! It is an array of pointers.
So the size of the structure is correct to be 0. No Bug.

Code: Select all

*st\arr = AllocateMemory(SizeOf(RECT) * 4)

This syntax in anyway wrong, because *arr.RECT[n] is not one pointer to an array with n-1 elements, it is an array of n-1 pointers.
*st\arr = ... is the sort version of *st\arr[0] = ...

Edit: Please do not post in "Bug Reports" if you have a code question.

Posted: **Fri May 17, 2024 11:37 am**

Please note, that in structures a @Bold "static array[]" doesn't behave like the normal BASIC array (defined using @ReferenceLink "Dim" Dim)
to be conform to the C/C++ structure format (to allow direct API structure porting). This means that a@Bold "["2@Bold "]" will
allocate an array from 0 to 1 where Dim a@Bold "("2@Bold ")" will allocate an array from 0 to 2. And library functions
@LibraryLink "Array" "Array" don't work with them.

PureBasic Forums - English

Weird struct sizeof with static arrays

Weird struct sizeof with static arrays

Re: Weird struct sizeof with static arrays

[no bug]Re: Weird struct sizeof with static arrays