Hi Juan, Thanks for the link! Some questions below: On Fri, Jun 16, 2017 at 8:23 AM, Juan Perez-Sanchez <lithoxs@xxxxxxxxx> wrote: > On Thu, Jun 15, 2017 at 5:19 AM, Edoardo <eddyx89@xxxxxxxxx> wrote: >> If I remember correctly, one of ELKS limits was that binaries had to >> fit on a 64KB page, and that was due to the compiler we used (dev86 / >> bcc). > > Actually, code size <= 64KB and separately (data + bss + stack sizes) <= 64KB. > >> Do you think/know if GCC may solve this limit, being able to produce >> multi-page binaries? > > No, those limits still holds. I guess there are both limits in the compiler and limits in ELKS itself, right? Alan kindly explained to me in the last few days in the thread http://www.spinics.net/lists/linux-8086/msg00813.html what kind of complex things ELKS would need to do to handle processes with multiple code segments and/or multiple data segments, and those restrictions are still there, so simply using GCC doesn't make them go away. The "Getting Started Guide" for this new IA16 GCC actually mentions a few limitations in this area that the new compiler has: - Section 3.2 says "Although this version of Sourcery CodeBench Lite uses ELF as its internal object format, it produces executables in DOS COM format." DOS .COM format implies a single 64KB segment for combined code and data, i.e. tiny memory model, right? That's more restrictive than ELKS. - Section 3.3 says "Far pointers currently do not work, so accessing memory outside the program's 64kB segment requires the use of assembly (either inline or a separate file that is assembled and then linked into the program).", so it's not going to let you make bigger executables even if ELKS added such support. For what it's worth you'd find far pointer support in OpenWatcom. I see that ia16-elf/lib/dos-com.ld seems to have some instructions related to making a DOS .COM file. I've never played with GCC linker scripts before, but I assume there's nothing in the compiler that would prevent it from generating a full 64KB code segment and also a full 64KB data segment, and one could make a linker script for generating an ELKS executable with those two separate segments instead of being limited to it all being in one segment like with a .COM file? Apologies in advance if I'm spreading any misinformation here! Thanks, David -- To unsubscribe from this list: send the line "unsubscribe linux-8086" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
