Hi!

Lately I spent some time debugging the internal error problem and it turns out that in method TCoffObjSection.fixuprelocs the .stabs section gets "damaged": AFAICT the data.write statement in that method tries to replace a 4-byte offset pointer with an 8-byte (RELOC_ABSOLUTE) one.

Hence, I'd propose to (a) add some check for the data size to the method

   data.Seek(objreloc.dataoffset);
   data.Write(address,address_size);
   if (data.size  Size) then
      <internal error>

and (b) there needs to be a patch for .stabs offsets (relocs) to be 4(?!) bytes only. To address (b) I tried to change TInternalAssembler.WriteStab(p:pchar) to use RELOC_ABSOLUTE32 but that did not seem to work. Also, I don't know whether the lines

                 if reloctype=RELOC_RELATIVE then
                   begin
                     if win32 then
                       dec(data,len-4)

in TCoffObjData.writereloc could potenially pose a problem. So in summing up, perhaps someone of the core-fpc developers can take over from here and do a fix for this problem?

TIA,
Willi

Also, I don't know whether the lines

Please ignore the above comment in my previous mail.

Cheers,
Willi

Proposed fix now in mantis, #0017500. Turns out RELOC_ABSOLUTE32 seems to work, I had forgotten to do a proper clean before checking.. :-\

Cheers,
Willi

Thank you so much!

It's been a while that I was trying to understand why stabs generation was messed up for win64 target.
Your suggestion is correct, I was able to
complete a cycle with DEBUG=1 using internal object writer and linker and get correct stabs information.
I will test a complete 'make clean all FPC=ppcx64 DEBUG=1' at fpcsrc level and check in the fix if it completes successfully.

Thanks again.

Pierre Muller

The complete compilation worked.

Patch committed in rev 16056 in trunk.

Thanks again!

Pierre

Wow, that was quick! Thanks for putting this into trunk in record time! Cool, now I've got a working FPC and can start hacking on Delphi-like package stuff :)

Cheers,
Willi

Willibald Krenn wrote

Wow, that was quick! Thanks for putting this into trunk in record time! Cool, now I've got a working FPC and can start hacking on Delphi-like package stuff :)

Keep us informed about your progress, please :D

Regards,
Sven