Warning D9035 option 'Gm' has been deprecated and will be removed in a future release

when I compile a legacy project in VC++ 2017, I ran into this message and take note here:

Warning D9035 option 'Gm' has been deprecated and will be removed in a future release

1. Command line warning D9035: option 'Gm' has been deprecated and will be removed in a future release

Try selecting for the Enable Minimal Rebuild option (under C/C++ > Code Generation). After this, the option should show No (/Gm-), not in bold. Make sure you do this for your project(s) (you could have several projects in the solution), and all property pages they inherit from.

I had the same problem using Visual Studio 2019, in the end the problem was in a second project I had in the same solution, that had the option set to Yes (/Gm).

2. /Gm (Enable Minimal Rebuild)

Deprecated. Enables minimal rebuild, which determines whether C++ source files that include changed C++ class definitions (stored in header (.h) files) need to be recompiled.

/Gm is deprecated. It may not trigger a build for certain kinds of header file changes. You may safely remove this option from your projects. To improve build times, we recommend you use precompiled headers and incremental and parallel build options instead. For a list of deprecated compiler options, see the Deprecated and Removed Compiler Options section in Compiler Options Listed by Category.