Visual Studio debugger not working for a DLL build from assembly source files?-CodePudding

I'm currently using masm in a C wrapper to develop a .dll so it can be used by other applications, notably a c# one in Visual Studio 2022

However developing this way has some big drawbacks. Visual Studio has all sorts of little niggles about getting MASM working such as building properly if a file is 'included' in the asm source. Such files also cannot have break points. This means I have to resort to one large file, which is getting very unwieldy.

Its like Microsoft have given up supporting MASM, unless there's some way to build a DLL that allows debugging?

Or is there some better way to develop x64 .dlls on Windows, if there's no easy fix for the Visual Studio debugging problem?

CodePudding user response：

Working example. I'm able to step through the c# code and into the assembly code. Directory for assembly based DLL is c:\xcadll.

xa.asm:

        includelib      msvcrtd
        includelib      oldnames        ;optional
        .data
        .data?
        .code
        public  DllMain
DllMain proc                            ;return true
        mov     rax, 1
        ret     0
DllMain endp
        include xb.asm
        end

xb.asm:

        public  Example
Example proc                            ;[rcx] = 0123456789abcdefh
        mov     rax, 0123456789abcdefh
        mov     [rcx],rax
        ret     0
Example endp
        end

Program.cs - used to call the debug version of the dll:

using System;
using System.Runtime.InteropServices;
namespace Program
{
    class Program
    {
    [DllImport("c:\\xcadll\\x64\\debug\\xcadll.dll")]
    static extern void Example(ulong[] data);

        static void Main(string[] args)
        {
            ulong[] data = new ulong[4] {0,0,0,0};
            Console.WriteLine("{0:X16}", data[0]);
            Example(data);
            Console.WriteLine("{0:X16}", data[0]);
            return;
        }
    }
}

Project settings for DLL build:

Create a .dll project for the assembly (or C or C ) code:

project properties: Debug | x64

properties for xa.asm:

General / Excluded From Build: No
Custom Build Tool / Command Line: ml64 /c /Zi /Fo$(OutDir)\xa.obj xa.asm
Custom Build Tool / Outputs: $(OutDir)\xa.obj

Project settings for C# build:

Create a C# project

project properties: Debug | x64

As shown in the example code above, the C# program needs to import the debug version of the DLL.