Pre-release check crashes extension if the response is invalid

[kucharski-s]

Environment

• OS and Version: Linux
• VS Code Version: 1.99.3
• C/C++ Extension Version: 1.27.7
• If using SSH remote, specify OS of remote machine: N/A

Bug Summary and Steps to Reproduce

Bug Summary:

The extension crashes with following error when reply from the server is invalid. Such situation can occur when held by a captive portal.

In our setup DNS is intercepted due to security restrictions and redirects to our server (like a captive portal would). This causes the extension gallery POST request get a 404 response with an HTML page.

2025-09-20 16:55:28.879 [error] TypeError: Cannot read properties of undefined (reading '0')
at Object.preReleaseCheck (/home/team/.vscode/extensions/ms-vscode.cpptools-1.27.7-linux-x64/dist/src/main.js:11970:50)
at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
at async activate (/home/team/.vscode/extensions/ms-vscode.cpptools-1.27.7-linux-x64/dist/src/main.js:117216:9)
at async cw.n (file:///usr/share/code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:111:13359)
at async cw.m (file:///usr/share/code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:111:13322)
at async cw.l (file:///usr/share/code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:111:12778)

This is the relevant line:

vscode-cpptools/Extension/src/main.ts

Line 81 in 5855d98

await LanguageServer.preReleaseCheck();

Steps to reproduce:

1. Run VS Code on machine with restricted Internet access.
2. Observe that the extension crashes.

Expected behavior:
The extension handles the error gracefully, as if no Internet was present.

Configuration and Logs

2025-09-20 16:55:28.879 [error] TypeError: Cannot read properties of undefined (reading '0')
        at Object.preReleaseCheck (/home/team/.vscode/extensions/ms-vscode.cpptools-1.27.7-linux-x64/dist/src/main.js:11970:50)
        at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
        at async activate (/home/team/.vscode/extensions/ms-vscode.cpptools-1.27.7-linux-x64/dist/src/main.js:117216:9)
        at async cw.n (file:///usr/share/code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:111:13359)
        at async cw.m (file:///usr/share/code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:111:13322)
        at async cw.l (file:///usr/share/code/resources/app/out/vs/workbench/api/node/extensionHostProcess.js:111:12778)

Other Extensions

No response

Additional context

No response

[bobbrow]

Thank you for reporting this. I have proposed a fix for it.

[sean-mcmanus]

@kucharski-s Fixed with https://github.com/microsoft/vscode-cpptools/releases/tag/v1.28.0 (pre-release).