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Posted: **Sat Jan 02, 2010 5:37 am**

Whether I use NASM or YASM I'm having a problem in which macros don't seem to generate anything for some reason.

I have tried putting them before the rest of the code but they keep. Even YASM reports them as undefined symbols if I try to use them in some code like this (because of the local label named .__1):

Code: Select all

   .__1:
   ___MACRO_push_rsp
   ___MACRO_pop_rsp

   mov eax,ebp
   cmp dword[eax+1_],2
   je .__1

They aren't reported as undefined if I use a global label (without a dot at the beginning of if).

My macros are something like this:

Code: Select all

%macro ___MACRO_push_rsp 0
 push esp


%endmacro



%macro ___MACRO_pop_rsp 0
 pop esp


%endmacro

But they don't generate code for some reason. It's as if they weren't included in the source files and if they are called more than once it's like defining a label and is reported as a redefinition.

It doesn't happen if I put the macros in a source file with macros only (no other definitions or db, dw, dd variables, etc.) and also if I put them before anything else in the program includes. Maybe it's like C with some definitions which need to be defined before first use?

Does anybody know what could be done or some further information I coud provide to solve this?

Posted: **Sat Jan 02, 2010 7:17 pm**

Did you remember to actually call the macros?
Just defining a macro does nothing to the final output, it needs to be invoked.

Example:

Code: Select all

%macro FRAME_INIT 0
push ebp
mov ebp, esp
%endmacro
%macro FRAME_CLOSE
pop ebp
%endmacro

function:
    FRAME_INIT
    ... do stuff
    FRAME_CLOSE
    ret

Posted: **Mon Jan 04, 2010 2:18 am**

I don't find anything wrong. You are defining the macro's before using them, arent't you? Maybe you'd better post the complete code.

OSDev.org

Why NASM macros don't generate code?

Why NASM macros don't generate code?

Re: Why NASM macros don't generate code?

Re: Why NASM macros don't generate code?