Chasing more 386 OMF

Microsoft’s first 32bit OS, Xenix

Well back before, I had been looking into old linkers for 386 OMF, I knew I’d found some fun with some old GNU tools going back to the heyday of Xenix 386. As kind of expected the tools used to build Xenix, along with it’s SDK were in fact Microsoft C/MASM. So yes way back in 1987 Microsoft not only has MASM386, but they also had a 32bit Microsoft C 5.00. Let that sink in for a moment as OS/2 had been forced into 16-bit land despite FOOTBALL, and Windows/386 being a 386 VM86 multitasker. So in a weird way all the parts were in existence.

Back in the old days of GCC 1.x there was a bit of excitement about the file masm386.c in the old GCC source directory, sadly despite it being updated, there was no real public push on modifying GCC to support non AT&T assemblers. Instead something unexpected (well to me!) happened is that GAS had been modified to output OMF.

I tested this on MinGW with some simple stuff, and sure enough it links just fine. Considering its what is on the GCC on Xenix port I’m sure it’s pretty solid.

Enter OS/2

Now this is more fun, and again kind of sad that GCC didn’t take on the ability to target other assemblers (just look at the x68000!), Maybe they didn’t see GAS for OMF, or just didn’t know. Instead a more aggressive choice was made, to alter the binary output. Linking on OS/2 with EMX involved 2 very different and incompatible paths, the first one is the ancient Unix i386 a.out format, which then a utility called emxbind will convert into a loader & stub that OS/2 can run. Think of it as an OS/2 extender to take simple Unix programs (which is what they are) to run on OS/2. Neat!

The second more ‘native’ approach is to convert the binary a.out files into what is known as OMF files, which non GNU linkers like Wlink from Watcom or Link386 from Microsoft can then link into direct native EXE’s or DLL’s.

There had been an experimental ELF build of the EMX toolchain on OS/2 but I think it may have died? So as crazy as it seems bigger and crazier programs need to be built on systems like Windows or Linux and linked outside of OS/2 to get around the old memory limits. It’s really hard to say as I’ve never used it, although being able to do the link outside of OS/2 would be an advantage.

I’ve found 2 programs to convert the a.out objects into OMF, the first and oldest being o2obj. The one drawback I’ve had is that this doesn’t play so well with the Watcom 386 OMF linker. Instead the much later RSXNT/LIBC0.6 project’s emxomf. I’ve done some painful hacking but it appears to do what it should do. A simple omfdump seems to be spilling stuff out.

Of course the alternative is to use a 64bit linker, and since a.out has been pulled from binutils the only real hope is the Watcom linker which is now running in a 64bit address space. And the Watcom chain won’t understand ancient i386 a.out, however Microsoft 386 OMF it certainly will, although it appears to be based around something later than the aforementioned o2obj, which is why I ahd to do the emxomf.

I know as this stands it’s not very satisfying but I kind of wanted to push this out the door as I’d been hacking from time to time on it, and didn’t want to leave it to rot completely. The EMX tools remind me of the NeXT stuff where everyone goes native platform wild never imagining a day when remaining portable would mean it’d be easier to target more software.

The one thing I wonder about sometimes if there was some kind of secret Microsoft extended DOS/Windows that relied on OMF & Link386 that predated the NT team and their switch to COFF? Obviously it’d be super obsolete and would have been something like the first PharLap 386 stuff. But I’ve only owned a disk dump of v4, and a legit copy of TNT v6. Old 386/DPMI/Extender tools are hard to find.

Linkers & loaders, along with binary formats are too hard for me, but I thought I’d share at least what I’d been able to conjure with MinGW. I’ll have to touch on EMX to native OMF linking later.

Annoyance with the MIPS linker: relocation overflows

gcc disasm.o audio.o configuration.o dialog.o file.o hostcall.o keymap.o main.o memAlloc.o misc.o screen.o screenConvert.o sdlgui.o shortcut.o scalebit.o input.o fe2.o ../fe2.part1.o ../fe2.part2.o -L/usr/lib/mips64el-linux-gnuabi64 -lSDL -o ../frontier

/usr/bin/ld: ../fe2.part1.o: in function <code>load_binfile': fe2.s.c:(.text+0x180): relocation truncated to fit: R_MIPS_CALL16 against</code>[email protected]@GLIBC_2.2'
/usr/bin/ld: fe2.s.c:(.text+0x19c): relocation truncated to fit: R_MIPS_CALL16 against <code>[email protected]@GLIBC_2.0' /usr/bin/ld: fe2.s.c:(.text+0x1a8): relocation truncated to fit: R_MIPS_CALL16 against</code>[email protected]@GLIBC_2.0'
/usr/bin/ld: fe2.s.c:(.text+0x1c0): relocation truncated to fit: R_MIPS_CALL16 against <code>[email protected]@GLIBC_2.0' /usr/bin/ld: fe2.s.c:(.text+0x1e4): relocation truncated to fit: R_MIPS_CALL16 against</code>[email protected]@GLIBC_2.0'
/usr/bin/ld: fe2.s.c:(.text+0x1f0): relocation truncated to fit: R_MIPS_CALL16 against <code>[email protected]@GLIBC_2.2' /usr/bin/ld: fe2.s.c:(.text+0x280): relocation truncated to fit: R_MIPS_GOT_DISP against</code>[email protected]@GLIBC_2.0'
/usr/bin/ld: fe2.s.c:(.text+0x284): relocation truncated to fit: R_MIPS_CALL16 against <code>[email protected]@GLIBC_2.0' /usr/bin/ld: fe2.s.c:(.text+0x290): relocation truncated to fit: R_MIPS_CALL16 against</code>[email protected]@GLIBC_2.0'
/usr/bin/ld: fe2.s.c:(.text+0x2b4): relocation truncated to fit: R_MIPS_CALL16 against `[email protected]@GLIBC_2.0'
/usr/bin/ld: fe2.s.c:(.text+0x2c4): additional relocation overflows omitted from the output
collect2: error: ld returned 1 exit status
make[1]: *** [Makefile:18: ../frontier] Error 1

I’d never heard or seen this before, and yeah it’s some MIPS’isim.

Apparently it’s something called a “global offset table” which of course has a 64k entery limit which can cause an overflow if you are doing something crazy like running a disassembler and having tens of thousands of instructions.

Looking at the GCC MIPS options page, there is hope, one can opt for a more iniffecient and larger table with the simple option of -mxgot

FrontVM-2 20061120

And now I can link frontvm.

Congruent (Toolbusters) GCC 2.4.5 for Windows NT

Perhaps one of the more interesting, if not abandoned GCC ports.

It’s from 1994 (although they apparently had earlier), and it’s just enough binutils & gcc to compile stuff for Win32.

I stumbled onto the directory http://www.nic.funet.fi/index/win-nt/gcc/ while looking for the source code to the ‘top’ program, which incidentally can be found here. In hindsight the name ‘top’ is pretty terrible, as looking at the ‘top program for Linux’, well you are going to find all kinds of crap, and surely not top.

The files gnu-bin.tar.Z and gnu-lib.tar.Z contain enough binaries for GCC 2.4.5 C/C++ and ObjectiveC, along with GAS and what purports to be a linker, although I think it just prints the flags to MS Link that you’d need.

And as mentioned in this post, by Juha Inkari, how on earth do you use this thing? Well thankfully in the future we have access to more stuff, so I decided to throw MinGW at it, and see what happens.

I’m using the Linker & LIBC from Fortran PowerStation 1.00 with the linker update.

There is no source diffs, patches, or anything really.

Is this useful? I suspect not. Thanks to RSXNT there is easier ways to get much older versions of GCC… Although I guess it speaks more so to this port using OMF objects.

Congruent Corporation
110 Greene Street
New York City, NY 10012
(212) 431 – 5100
(212) 219 – 1532 (f)

Anyone ever heard of Congruent? Sounds almost Cygnus like.

I think I’m chasing a struct packing issue

i386 breaking on the AASTINKY texture

On the i386 a texture info lump loads up just fine. However on a big endian G5…

OS X 10.2.8 on the G5 on the same AASTINKY

…It clearly has problems. Although notice that the positions and sizes are the same, as they ought to be.

Notice how originx is 24, which should be the width. This code was running with GCC 1.30/1.40 hammered x68000 GCC. Although I have been unable to get the much vaulted gcc-1.30.atari.tar.bz2 to do anything useful, well until tonight, when I found this file: GNU_HEAD.ARC.

That’s right, it’s the gcc-1.23 release headers for GCC on the Atari ST. Now I know other places people have been saying I should use MINT or some GCC8 port. And I wanted something to run on bare TOS, and I cross compiled the simple Infocom interpreter but it just crashes out after a few commands. It’s hardly stable.

3 bombs and an exit under GCC 8.0

Which is just a damned shame, as it was easier to just download someone else’s work.

Anyways, I now can build the old gcc-1.30 libc however… the linker that I’m using that works for GCC 2 links away and it looks like a working program but it doesn’t do anything. I have a feeling the linker drifted in those years between GCC-1.30 and GCC-2.something when it was adapted. Certainly by the time of 2.5.8. So yet more endian ghosts to chase down if I try to adapt that linker.

Building MAME 0.1 for MS-DOS / DJGPP

So as promised, a while back I had built a GCC 2.7.2.3 / Binutils 2.8.1 cross compiler toolchain suitable for building old Allegro based programs, such as MAME.  Of course the #1 reason why I’d want such a thing is that being able to do native builds on modern machines means that things compile in seconds, rather than an hour + compiling inside of DOSBox.

Why not use a more up to date version of both GCC/Binutils?  Well the problem is that the pre EGCS tools ended up with macro and inline assembly directives that were dumped along the way so that later versions simply will not assemble any of the later video code in Allegro, and a lot of the C needs updating too.  And it was easier to just get the older tool chain working.

It took a bit of messing around building certain portions inside of each step of the tools, but after a while I had a satisfactory chain capable of building what I had needed.

So for our fun, we will need my cross DJGPP v2 tool chain for win32, MAME 0.1, Allegro 3.12 and Synthetic Audio Library (SEAL) Development Kit 1.0.7 .

Lib Allegro is already pre-built in my cross compiler tool chain, all that I needed to add was SEAL, with only one change, 1.0.7 is expecting an EGCS compiler, which this is not, so the -mpentium flag won’t work, however -m486 will work fine.

Otherwise, in MAME all I did was alter some include paths to pickup both Allegro and SEAL, and in no time I had an executable.  And the best part is checking via DOSBox, it runs, with sound!

MAME 0.1 on DOSBox PACMAN hiding

Thankfully MAME has been really good about preserving prior releases, along with their source tree, and it’s pretty cool to be able to rebuild this using the era correct vintage tools, and I can’t stress how much more tolerable it is to build on faster equipment.

MinGW and missing DLL’s

UGH

Stuff like this drives me crazy.  Once upon a time everything was statically linked, there were no DLL’s, and all exe’s had a lot of the same code in them, and people realized that the majority of a hard disk could literally contain the same thing over and over.  Not to mention that if you were to fix some bug in say, LIBC you would have to re-compile everything.  So we entered the brave new world of dynamic linking where we now live in the proverbial DLL hell, that although we did save space, we have things where slight variations in the same DLL can break things in unforeseen ways.  People have tried various things such as weak linking, Side by side assemblies, Frameworks, and all kinds of things to try to keep things together.

Honestly it’s just easier to go back, and statically link things, and just re-build as needed.

common culprits of MinGW based stuff always include:

  • libwinpthread-1.dll
  • libgcc_s_dw2-1.dll
  • libstdc++-6.dll

ugh.

The hard one is the pthread library.  If you try to link it statically it’ll try to link everything else statically and not every DLL can link statically (SDL* keep reading).  But GCC / Binutils does have the option to turn various features on and off through the link string

-static-libstdc++ -static-libgcc -Wl,-Bstatic -lstdc++ -lpthread -Wl,-Bdynamic

As you can see, everything after “-Wl,-Bstatic” will be linked statically, while everything after “-Wl,-Bdynamic” will go back to being dynamically linked.

Ok, that is great but what about SDL, you may ask.  Well sure it’s a DLL, but even DLL’s come from somewhere.  Download the source, build it yourself and you can directly link the objects that make up the DLL.  In version 1.2.15 they live in the .libs directory.

SDL-1.2.15\build\.libs\*.o

And on Windows, if you get weird errors like:

SDL_dx5events.o: In function `DX5_DInputInit’:
SDL-1.2.15/./src/video/windx5/SDL_dx5events.c:183: undefined reference to `IID_IDirectInputDevice2A’

Just add the -ldxguid library and you can link this too.  I’m sure once upon a time people may not have had DirectX 5 or higher, but this isn’t 1997.

And please at least test your programs with no path, so that way you are aware of what is needed for re-distribution.

set path=.
D:\dosbox-code-0-4068\dosbox\trunk\src>dosbox.exe

DOSBox SVN

It gets so old when people never test.  And people freak out trying to download DLL’s from weird sites, and you know that never ends well.

Oh yeah, and a static version of DOSBox is 4MB.

4,033,550 dosbox.exe

I know that was massive a long long time ago, but today?

26th anniversary of Linux!

As the joke goes:

Happy 25th birthday, Linux! Here’s your f-ing cake, go ahead and compile it yourself.

So it’s always a fun time for me to push my old project Ancient Linux on Windows.  And what makes this so special?  Well it’s a cross compiler for the ancient Linux kernels, along with source to the kernels so you can easily edit, compile and run early Linux from Windows!

As always the kernels I have built and done super basic testing on are:

  • linux-0.10
  • linux-0.11
  • linux-0.12
  • linux-0.95c+
  • linux-0.96c
  • linux-0.97.6
  • linux-0.98.6

All of these are a.out kernels, like things were back in the old days.  You can edit stuff in notepad if you so wish, or any other editor.  A MSYS environment is included, so you can just type in ‘make’ and a kernel can be built, and it also can be tested in the included Qemu.  I’ve updated a few things, first with better environment variables, and only tested on Windows 10.  Although building a standalone linux EXE still requires a bit of work, it isn’t my goal here as this whole thing is instead geared around building kernels from source.  I included bison in this build, so more of GCC is generated on the host.  Not that I think it matters too much, although it ended up being an issue doing DooM on GCC 1.39.

So for people who want to relive the good old bad days of Linux, and want to do so from the comfort of Windows, this is your chance!


Download Ancient Linux on Windows
Download Ancient Linux on Windows

Null DooM, GCC 1.39, GO32 and DPMI


phew.

DooM via DJGPP v1 GO32

Around the time of the x68000 port of DooM, I was cutting down the DooM source for a null/portable version.  I never could get it to actually run either using EMX or  DJGPP 1.03, as I couldn’t get it to link to save my life with a constant never ending battle of unresolved symbols. After a while I just used what I had towards the x68000 version and concentrated on getting it up and running, and just shelved the null/portable effort.

Later on I wanted to get it running again as part of messing with another cross compiler, as DooM isn’t a trivial application to port and verify correct operation. And in the process of trying to get the null version to build and run on Windows using TDM GCC, I wanted to make sure it at least kept compiling with GCC v1.x.

Once more again I was able to compile individual files but unable to link.  But this time, I just looked at the diffs for binutils, I thought it should be somewhat easy to get hosted on Windows.  Although versions may point to binutils 1.0, I had to use binutils-1.9.tar.gz even though the diffs are against Mar 24 1991, and the source for 1.9 is dated April 17 1991.

My first effort gave me a linker that would happily link, but go32 would either refuse to run the executable, or just crash.  I was going to give up again, but I found mention in another file that DJGPP actually uses the linker from G++, the C++ compiler which was a separate thing in the late ’80s and early’90’s.  This time it worked, and I could link a trivial hello world style application!

Now that I finally had a cross linker actually working, I didn’t want to compile under emulation, so looking at the other diffs, they didn’t look too extensive. I went ahead ,and took DJGPP v1.06 and patched up the compiler & assembler to get a full cross toolchain.  And in no time, I had a null version of DooM running on MS-DOS well at least tested on DOSBox.

This was fun, and all but I didn’t see any easy way to do fun things like hook interrupts so I could get the keyboard & clock like any good MS-DOS program.  DPMI greatly eased this kind of stuff, so looking at the DJGPP history, DJGPP v1 version 1.10 actually adds preliminary DPMI support!  And in the next version, DPMI was much more better supported, however the binary format had changed from a.out to COFF as part of the move to v1.11. I was able to take the memory, and DPMI portions from the final v1.12 libc, and manually build and run them against the v1.06 library / dev tools.

And much to my surprise, it actually worked!  At least having the wrong format didn’t have any effect on how GO32 worked for me.

So feeling lazy, I snagged some of the support code from Maraakate’s revamp of DooM, just to make sure of the timer code, and the keyboard code, and again verified that I can build with the keyboard & timer ISR and I’m able to play the v1.9 shareware & commercial levels fine.  I haven’t done a thing to clean up or update the DooM source itself against all the dozens of bugs and issues with Ultimate DooM, or other games like Chex Quest etc.

I’m sure 99% of people wouldn’t care but you can download it here:

Win32_DJGPPv1_DooM.7z
Download crossdjgppv1

Although I’m using DPMI to drive realtime events, if I looked further at the GO32 v1.06 environments I could either figure out how it operates it’s timer, or modify the extender directly to drive the PIC timer and keyboard as I need.  But overlooking that, the vintage 1991 software is more than capable of running DooM.

Found some more ancient GNU software

I found a bunch of them here: ftp://ftp.ne.jp

CVS brows of the following:

I didn’t know that GNUmake 2.9 and prior was actually part of binutils.  I guess at some point I’ll build the older ones on 4.2 BSD to round out the experience.

And I don’t know where to find Emacs 18.41 and going further back.  Although I did find emacs1855.taz a DECUS (Digital Equipment Computer Users’ Society) image from late 1989.