Assembling Gravity Force 2 source code

[absence]

As some of you know, the source code for Gravity Force 2 is available on its home page. Is it difficult to assemble it and get an executable that is byte for byte identical to the one that can be downloaded? According to the documentation the code was written using "Seka, AsmOne, Trash'm-One". I assume these were used at different points in time, and not simultaneously. Which assembler is the most likely to have been used for the final version? Are there any special things to take into consideration if I want an identical executable? Are any of the newer/retargetable assemblers (Phxass, Vasm, others?) compatible enough for this?

[Leffmann]

They most likely used ASM-One, it was still in development years after Seka and Trash'm-One had faded. I haven't tried assembling the game, but Vasm has an ASM-One compatibility mode that should do the trick.

[absence]

Originally Posted by Leffmann

They most likely used ASM-One, it was still in development years after Seka and Trash'm-One had faded. I haven't tried assembling the game, but Vasm has an ASM-One compatibility mode that should do the trick.

Thanks! I'm looking at the Vasm docs, but the only compatability options I've found are for Devpac and Phxass. I'll try the actual ASM-One. Btw, the source files all have some binary garbage at the beginning. Is that normal?

[absence]

Originally Posted by absence

I'll try the actual ASM-One.

I've tried v1.20 and v1.48, and Trash'm-One v2.0. They all complain about illegal operator in some dc.b (line 3266 in gfap.s).

[Leffmann]

The garbage is probably from ASM-One, it saves its settings in the beginning of the source file like that, but I think they might actually have used SEKA to assemble it.

In any case it was easiest to make it assemble with Vasm, but it seems their executable was built from a different source archive as there are files missing etc.

[absence]

Thanks! It's nice to see how little change is needed to make it assemble with a modern tool. I notice you've inserted a lot of tabs, and that fixes the errors I got as well. Got curious and eventually found out there's a "Labels:" setting that makes the code assemble without tabs or other changes in TrashemOne. Oh well, now to conduct experiments!