DOS ain't dead

Debugging and mapping functions (MS Linker) (Developers)

posted by lifelike, 20.03.2025, 20:59

Hello!

My first post. I am making slow progress on a problem, and was thinking
that if I post about it here maybe someone that knows more about this
stuff than me has something clever to say about it.

Trying to debug something in code that I compiled and linked using the toolchain that Microsoft posted last year together with the source code of MS-DOS 4.0 (here: https://github.com/microsoft/MS-DOS/tree/main/v4.0/src/TOOLS).

The debugger I used for now is the one built into DOSBox-X (similar, I believe, to the one in the original DOSBox). It is difficult since I can't figure out the location of my functions (or data).

The linker (Microsoft Overlay Linker 3.65) generates a MAP-file that is mostly just lines like this:
1286:0BA2 _flip5
1286:0B7E _flip_range
31A6:3584 _flist_sel
1286:0E2C _fli_abs_tseek
21E5:0130 _fli_comp1
301E:0068 _fli_comp_frame

Very simple and nice file format, but quite useless without some tool that can tell me where each function ends up after I run the EXE and functions are relocated? Is there some free debugger that may be able to help? Or some trick to do this using the debugger in DOSBox? Setting breakpoints without knowing where the functions are is quite tedious.

I have resorted to breaking at interrupts instead and it works, but it would be more convenient to have a DOS debugger where I can just break at named functions.

Suggestions?

Complete thread:

• Debugging and mapping functions (MS Linker) - lifelike, 20.03.2025, 20:59 (Developers)
  • Debugging and mapping functions (MS Linker) - alexfru, 21.03.2025, 05:02
    • Debugging and mapping functions (MS Linker) - lifelike, 21.03.2025, 20:15
      • Debugging and mapping functions (MS Linker) - tom, 22.03.2025, 21:58
        • Debugging and mapping functions (MS Linker) - lifelike, 25.03.2025, 23:16
          • Debugging and mapping functions (MS Linker) - Japheth, 26.03.2025, 05:03
            • Debugging and mapping functions (MS Linker) - marcov, 26.03.2025, 11:03
            • Debugging and mapping functions (MS Linker) - lifelike, 27.03.2025, 20:02
          • Debugging and mapping functions (MS Linker) - ecm, 26.03.2025, 09:59
  • Debugging and mapping functions (MS Linker) - Rugxulo, 21.03.2025, 06:20
    • Debugging and mapping functions (MS Linker) - lifelike, 21.03.2025, 20:12