Bug in struct macro

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LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4633
Location: Argentina

LocoDelAssembly

(Not really related to fasm internals)

There is a bug in struct macro of win32 package.

Code:

  struct WBB
    word dw ?
      struct
        byte1 db ?
        byte2 db ?
      ends
  ends

alpha WBB

mov dl, [alpha.byte2] ; Works
mov al, [ebx+WBB.byte1] ; Works

However:

Code:

 struct WBB
   union
     word dw ?
       struct
         byte1 db ?
         byte2 db ?
       ends
   ends
 ends

alpha WBB

mov dl, [alpha.byte2] ; Works
mov al, [ebx+WBB.byte1] ; Error: undefined symbol 'WBB.byte1'

28 Dec 2007, 02:49

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 17271
Location: In your JS exploiting you and your system

revolution

It is documented, you cannot have structs in anonymous unions.

28 Dec 2007, 05:20

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4633
Location: Argentina

LocoDelAssembly

http://flatassembler.net/docs.php?article=win32 <- Where it says that?

Also note that the documentation has a more complex example:

Code:

  struct LINE
    union
      start POINT
      struct
        x1  dd ?
        y1  dd ?
      ends
    ends
    union
      end   POINT
      struct
        x2  dd ?
        y2  dd ?
      ends
    ends
  ends

28 Dec 2007, 05:29

bitRAKE

Joined: 21 Jul 2003
Posts: 2913
Location: [RSP+8*5]

bitRAKE

replace union with struct and the same error results.

28 Dec 2007, 05:45

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4633
Location: Argentina

LocoDelAssembly

Seems that nesting is not properly supported for offsets constants (struct_name.field), however works correctly when you define a variable and access the fields throught variable name (var_name.field).

28 Dec 2007, 05:50

Tomasz Grysztar
Assembly Artist

Joined: 16 Jun 2003
Posts: 7721
Location: Kraków, Poland

Tomasz Grysztar

I've got it fixed (hopefully) with today's update.

01 Mar 2009, 18:06

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