Adding Assembly (asm) Files to Visual Studio C/C++ Projects

Step 0

Create a new empty C/C++ project and add some C/C++ source code or open an existing project.

Step 1

Go Project -> Build Customization...

Step 2

In the Visual C++ Build Customization Files dialog, tick masm(.targets, .props) and click on OK.

Step 3

Right click Source Files, choose Add, then New Item...

Step 4

In the Add New Item dialog, select C++ File (.cpp), and name the file with a .asm extension, then click Add. NOTE: that the .asm extension is important.

Step 5

Write some asm code.

Step 6

Update main.c to call the new asm function.

Step 7

Everything should work.

Step 8

If you have issue, check the .asm file by right clicking, and going Properties.

Step 9

In the dialog, ensure Item Type is Microsoft Macro Assembler then click OK.