A.D.A. Amiga Demoscene Archive

I'm using Bartman's toolchain and I'd like to use gcc/ld to compile and link in order to get some benefits from its link time optimizations (-flto) or other.whole program optimizations.

The demo has a mix of c and asm object files. Both vasm and gcc outputs elf object files:

When linking with vlink everything works fine. vlink invocation:


But when linking with gcc or ld the demo crashes when entering certain asm files. If I rewrite those asm files to be pc relative it seems to fix the issue. However, I'd like to know whether I'm just missing some option for ld/gcc that could fix this rather than having to make all my old cranky asm pc relative? (vlink doesn't require this for sure)

Here is my linker invocation:


Any idea? What parameters are you using?

Found a solution by using vlink to convert the final linked (and presumably link time optimized) elf file output from gcc to hunk format



Elf2hunk may have a limitation or bug

After enabling -flto -fwhole-program the demo exe size reduced from 171K to 156K crunched. There were some complications in that the __start function (that calls main) got eliminated and when forcing it to be present by telling the compiler it is used it still got moved away from address 0 in the exe file.

I solved this by omitting the __start from the main compilation and linking and adding it back in the final vlink conversion step :) A bit ugly.

I tried using the --entry=__start option in gcc and the -e option in vlink to set another start address than 0 for the exe, but it didn't seem to have any effect.

Currently I use version 13.2 of GCC, I compile a single C/C++/ASM file to make the executable. If I only use one cpp file, this cpp file includes all the .h and other .cpp files, it's a big blob which allows me to do rebuilds in less than 2 seconds.

I also use -flto but it shouldn't optimize much given my blob architecture. I'm not sure this will help you since I don't use Vasm but I give you my link command

Thanks! I think a single file with all cpp/h put into one could be a good solution.

While the stuff I wrote above works when using -std=c99 it actually causes some weird errors when I set std=c++11 or later. The linker errors report "stray [unicode] character in file", but the files in question are .o files. *shrug* Not sure what is going on.

We also used Bartman's toolchain for The Loop and incorporated vasm into the mix, but without neither calling vlink, nor m68k-amiga-elf-ld explicitly.

We also we forced vasm to produce elf-output from our sources as well and threw it all at gcc. Here is our makefile: makefile m68k-amiga-elf-gcc w. vasm -Felf

Thanks a lot! If it worked for you it should work for me as well. I also output elf from vasm in the current build. Maybe I need to upgrade some of the tools. I haven't looked at a new vasm for ages.