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Index > Compiler Internals > FASM's -d cmdline option

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Japheth



Joined: 26 Oct 2004
Posts: 151
Japheth 21 Feb 2008, 05:18
Hello,

I wanted to use FASM's new -d option, but run into a problem.

The source (template.asm) is

Code:
;--- FASM template source to define an import (template.asm)

 format COFF
    
macro defext name
{
  extrn name
    public __imp__ # name
__imp__# name dd name
}

      section '.data' data
      defext ?IMP
    


and FASM is launched with

fasm -d ?IMP=_AllocConsole@0 template.asm

but the symbol ?IMP is not changed to "_AllocConsole@0" in the resulting .OBJ file, it is still "?IMP".

Is -d supposed to define numeric values only?
Post 21 Feb 2008, 05:18
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 20414
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revolution 21 Feb 2008, 05:30
I haven't tried it but I imagine that "-d ?IMP=anything" is the same as doing "define ?IMP" at the first line in the source?
Post 21 Feb 2008, 05:30
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Japheth



Joined: 26 Oct 2004
Posts: 151
Japheth 21 Feb 2008, 05:38
revolution wrote:
I haven't tried it but I imagine that "-d ?IMP=anything" is the same as doing "define ?IMP" at the first line in the source?


Yes. Apparently it isn't really a problem with the -d option, it's more a problem with the '#' operator in macros, because the "extrn name" uses the externally defined name, but 'imp__#name' ignores it.
Post 21 Feb 2008, 05:38
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Tomasz Grysztar



Joined: 16 Jun 2003
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Tomasz Grysztar 21 Feb 2008, 10:24
See manual, section 2.3.7 for explanations.
Post 21 Feb 2008, 10:24
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Tomasz Grysztar



Joined: 16 Jun 2003
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Location: Kraków, Poland
Tomasz Grysztar 04 Mar 2008, 06:16
In other words, you just need to use "match" directive in order to concatenate the value of symbolic constant to some other value:
Code:
macro defext name
{
    extrn name
    match realname,name
    \{ public __imp__ \# realname
       __imp__# name dd realname \}
}    

You may find also these articles interesting, the are planned to become the part of Understanding fasm (which also may be helpful to explain how the # operator works).
Post 04 Mar 2008, 06:16
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Japheth



Joined: 26 Oct 2004
Posts: 151
Japheth 04 Mar 2008, 11:06
Tomasz Grysztar wrote:
In other words, you just need to use "match" directive in order to concatenate the value of symbolic constant to some other value:
Code:
macro defext name
{
    extrn name
    match realname,name
    \{ public __imp__ \# realname
       __imp__# name dd realname \}
}    



using match directive does the job, thanks!

btw, the availability of the -d option makes a -q option (to suppress the display of the "logo" and the "passes") useful now.
Post 04 Mar 2008, 11:06
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Tomasz Grysztar



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Posts: 8356
Location: Kraków, Poland
Tomasz Grysztar 04 Mar 2008, 11:07
Japheth wrote:
btw, the availability of the -d option makes a -q option (to suppress the display of the "logo" and the "passes") useful now.

No problem.
Post 04 Mar 2008, 11:07
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rugxulo



Joined: 09 Aug 2005
Posts: 2341
Location: Usono (aka, USA)
rugxulo 04 Mar 2008, 14:31
[quote="Japheth"]
btw, the availability of the -d option makes a -q option (to suppress the display of the "logo" and the "passes") useful now.
[/quote]

How so?

(BTW, thanks to Tomasz for helping him.)
Post 04 Mar 2008, 14:31
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Japheth



Joined: 26 Oct 2004
Posts: 151
Japheth 04 Mar 2008, 16:28
Quote:
Quote:

btw, the availability of the -d option makes a -q option (to suppress the display of the "logo" and the "passes") useful now.


How so?


Because -q is the only option which you can get by mirroring -d.
Post 04 Mar 2008, 16:28
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