Leu Icaros64

Paolo Besser works on a 64bit Version of Icaros (see also his website about it). I only try my AROS64 bit FreePascal stuff with my old linux hosted AROS 64 version, and there it worked fine. But the ABI of x64 AROS is not fixed yet, so still changes can happen. And there are some changes, Leu for example crashes on the Icaros64 alpha version, Paolo sent me. It crashes very early in the startup code. I started to debug that stuff but it’s very hard to debug at this point, that early in the startup. But my initial guess was more or less right, because the AROS devs tried to implement SMP they changed a lot of structures for additional locks and so on, so the Offsets of fields are moved. Usually an easy job just compare the the new C includes with my pascal counter parts. but it makes it much harder if defines and alignment comes to play, here also. The define was easy, there is a __AROSSYSTEM_SMP__ define which seems to be always enabled, even AROS is not compiled for SMP use (seems still too unstable) which includes and additional spinlock_t to MsgPort and Sempahore, so far so well. But it seems this spinlock_t is huge, by the definition I would say an Integer and a Pointer, but the size needed in the structure to cover up the missing offset shift is much more… something around 256 bytes. The structure is 128 aligned, this could be a key for that.

Usually that is not hard to find out, just make a small C program and test the sizes and offsets of the related structs, but… who have guessed it … on Icaros64 that is not that easy, because the gcc installed does not work, it just crashes. And btw. collect-aros, which we need fore linking in FreePascal also crashes, so for sure no compiling directly on the system.

But just by try and fail/crash and comparing the results of process and task structure to the output of Scout I got a somehow working version, it’s a very dirty hack, but for now it works, Leu works, FPC works (until collect-aros crashes when try to link, but without linking, everything is fine), FP-IDE is working (with the same problem like FPC of course).

There is some more work to really make that structures correct, but for that I will wait until the gcc is working again. The described way to compile stuff for 64bit in C on the icaros webpage using metamake is hilarious if you just want to compile a hello world it’s way overblown. I tried it, but it does not work, also compiling AROS64 from source does not work, I guess you need some pesky parameter when calling configure which, of course, are not described.