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Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library

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dn. Fri, 4 Aug 2023 08:31:49 +0200, R.Wieser napisał:
> Could you add a command like "lea ax,main" and see which address
> "main" gets translated too ?  It should ofcourse show 0x0100.  If it
> does not not than the linker didn't generate a COM style file to
> begin with.

Here it is:

00000005  8D060000          lea ax,[0x0]

Not unexpectedly, main() starts at offset 0 because the linker does not
compute the addresses with an extra +0x100. Which is the whole issue.

> Also, have you checked the binary contents of your (supposed) .COM
> file ? If it starts with "MZ" ...

The disassembly I posted in the initial message truly is the entirety
of the generated file. It starts with push bx. No "MZ" nor any other
header.

It appears that without startup code, wlink simply won't generate a
proper COM. Then one can either rely on the (huge! 1K) startup provided
by Watcom, by using the "SYSTEM COM" wlink directive, or hand-craft its
own startup code that would mimic whatever the original startup needs
to set up. In other words, I take there is no easy way to achieve what
I was looking for.

Mateusz

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[OpenWatcom] building a COM file without pulling in the Watcom standard library Mateusz Viste <mateusz@x.invalid> - 2023-07-31 17:28 +0200
  Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library JJ <jj4public@outlook.com> - 2023-08-01 18:38 +0700
    Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library Mateusz Viste <mateusz@x.invalid> - 2023-08-01 14:50 +0200
      Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library T. Ment <t.ment@protocol.invalid> - 2023-08-01 15:23 +0100
  Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library "Alexei A. Frounze" <alexfrunews@gmail.com> - 2023-08-02 20:28 -0700
    Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library Mateusz Viste <mateusz@x.invalid> - 2023-08-03 10:21 +0200
      Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library "Alexei A. Frounze" <alexfrunews@gmail.com> - 2023-08-03 19:41 -0700
        Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library Mateusz Viste <mateusz@x.invalid> - 2023-08-04 14:03 +0200
  Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library "R.Wieser" <address@is.invalid> - 2023-08-03 10:39 +0200
    Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library Mateusz Viste <mateusz@x.invalid> - 2023-08-03 12:07 +0200
      Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library "R.Wieser" <address@is.invalid> - 2023-08-03 14:35 +0200
      Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library "R.Wieser" <address@is.invalid> - 2023-08-04 08:31 +0200
        Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library Mateusz Viste <mateusz@x.invalid> - 2023-08-04 14:03 +0200
          Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library "R.Wieser" <address@is.invalid> - 2023-08-04 16:29 +0200
            Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library Mateusz Viste <mateusz@x.invalid> - 2023-08-04 16:56 +0200
              Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library "R.Wieser" <address@is.invalid> - 2023-08-04 19:02 +0200
                Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library Mateusz Viste <mateusz@x.invalid> - 2023-08-04 21:18 +0200
  Re: [OpenWatcom] building a COM file without pulling in the Watcom standard library Mateusz Viste <mateusz@x.invalid> - 2023-11-10 00:19 +0100

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