FASM $ keyword

It is my understanding that the $ keyword in FASM is equal to the current location during assembling, and in fact on http://en.wikibooks.org/wiki/X86_Assembly/FASM_Syntax the following example is given:

mystring           db    "This is my string", 0
mystring.length    equ   $-mystring

However, when placing two of these blocks back to back, I get wildly unexpected results:

a          db 'Hello, world! A'
alength    equ $ - a
b          db 'Hello, world! B'
blength    equ $ - b

alength now equals 30, whiles blength equals 20. Expected result is 15 for both.

Anybody know what could be happening?

LOL LACK OF NULL TERMINATION

Actually, just after posting this thread (even though I was trying to figure out the problem for around 3 hours before resorting to this), I managed to figure it out.

It seems like the equ directive now actually inserts its value at the place where it's used, and that position is used for calculation - so if I used alength later on in the code, it was actually using that position for its $ calculation.

Changing the code to this fixes it:

a          db 'Hello, world! A'
alength    db $ - a
b          db 'Hello, world! B'
blength    db $ - b

but requires me to use [alength], and is now actually treated as a memory address instead of a precompiler constant.

>>2
Waste of a byte...

>>3
Oh, it seems my manual was outdated.

The new syntax is

alength = ($ - a) and works fine

Use NASM instead.