Debug as C/C++ Container Application stuck at "Starting gdbserver"

[lukasdietz]

Describe the bug
Debugging an application inside a docker container gets stuck at the progress "Starting gdbserver".
Using a different debug target connecting to the already running gdbserver within the container (without building and uploading) works as expected.
The issue appears to be that the build/debug launch task blocks further execution of the debugger, preventing the connection from being established.

To Reproduce
Steps to reproduce the behavior:

1. Pull a docker image with gcc, g++, make and gdbserver installed
2. Create C/C++ Hello World Project
3. Setup "Build inside Docker Image" in project settings -> C/C++ Build -> Settings -> Container Settings
   • Enable "Build inside Docker Image"
   • Select local docker socket
   • Select previously pulled image
4. Build project inside docker container to ensure the environment is set up correctly
5. Try to debug application as C/C++ Container Application
6. Process hangs at "Starting gdbserver" and thus gdb is not connecting

Note: Starting the container in privileged mode does not change the behaviour.

Expected behavior

1. Starting a docker container mounting the project
2. Run gdbserver with specified arguments
3. Connect to running gdbserver
4. Running debugging session

Version Information (please complete the following information):

• OS and OS Version/extra details: Debian 13.5
• Eclipse Version: 2026-03 (4.39.0)
• CDT Version: 12.4.0.202603041756