Microsoft C/C++ Extension appears to no longer support unofficial forks of VS Code

[ImagineBaggins]

As of the latest update of Microsoft's C/C++ extension (v1.24.5, released April 3, 2025), use on non-Microsoft products appears to have been blocked. Upon initializing the extension, I get the follow error notification:

Text:

The C/C++ extension may be used only with Microsoft Visual Studio, Visual Studio for Mac, Visual Studio Code, Azure DevOps, Team Foundation Server, and successor Microsoft products and services to develop and test your applications.

I realize this is not a fault of VSCodium, but I figured I would bring this to the dev team's attention since this seems like a pretty severe issue and haven't seen any other mention of it in this repo or the repo of the C/C++ extension. I found one other recent mention of this issue on another project: getcursor/cursor#2976. Might also be related to the following Discussion, but it was created about a week ago, and this new issue has only presented itself (to me) today (April 4th) after the extension was updated: #2286.

For now, I have downgraded to the previous version (v1.23.6) and disabled Auto Update. Hopefully something can be done to remedy this.

VSCodium version: 1.96.4.25017
Platform: Windows 10 (22H2, 19045.5608)

[daiyam]

Hopefully something can be done to remedy this.

Sadly, it's a licensing issue. Now, they are just enforcing it by having the extension checks the editor it runs in.

Only an open-source alternative would be a viable solution.

[ImagineBaggins]

Sadly, it's a licensing issue. Now, they are just enforcing it by having the extension checks the editor it runs in.

Only an open-source alternative would be a viable solution.

Could the official extension be forked and simply remove this check? The extension is open source IIANM. Or maybe an unofficial build is all it would take? The main license (https://github.com/microsoft/vscode-cpptools/blob/main/LICENSE.md) seems to indicate that the restricted proprietary license is only a part of the final Microsoft-built-and-distributed files.

[VixiKitsune]

Sadly, it's a licensing issue. Now, they are just enforcing it by having the extension checks the editor it runs in.
Only an open-source alternative would be a viable solution.

Could the official extension be forked and simply remove this check? The extension is open source IIANM. Or maybe an unofficial build is all it would take? The main license (https://github.com/microsoft/vscode-cpptools/blob/main/LICENSE.md) seems to indicate that the restricted proprietary license is only a part of the final Microsoft-built-and-distributed files.

Seems like it can be

[daiyam]

The extension is open source IIANM.

Yes

Let's me try.

[daiyam]

There 3 closed-sources binaries cpptools, cpptools-srv and cpptools-wordexp. The 2 first ones are quite big.
Not quite sure what's they doing...

[MinecraftFuns]

It's impossible (or at least not possible to do publicly). The official extension consists of two parts: the TypeScript component, which is open source but not particularly interesting, and the binary files that perform the actual work. As @daiyam mentioned, these binary files are proprietary, and their runtime licenses specifically prohibit decompilation.

The environment check code is definitely in these closed-source binaries, as a thorough check of the open-source TypeScript code revealed no verification logic beyond the warning message.

[MinecraftFuns]

BTW a similar environment check exists in Pylance, which has prevented it from working with any forks of VS Code for many years. So far, no one seems to have found a solution other than resorting to alternatives.

[MinecraftFuns]

If the official build process is indeed as described in this comment, then replacing the product.json file with one extracted from the official distribution should work. However, I've tried this without success.

[VixiKitsune]

What about making VS Codium appear as official VS Code to the extensions?

[M2rsh]

Another day another disgusting move by Microsoft

[craigphicks]

What is the equivalent of the MS C++ extension with Intellisense in vsCodium ?

[SergioFLS]

if anyone is looking for a FOSS alternative then seems like clangd works well enough for a replacement

[wyahiaoui]

I am not sure whether it is related to this issue but since few days, the java testing extension are not working anymore inside VsCodium