Converting CDT 2.x Managed Make Projects
For a CDT 2.x Managed Make project, the Managed Build system will prompt you to convert your project when it attempts to read the Managed Build project information and discovers that the project needs to be updated. You will be prompted to update the project.
Click Yes and the project will be updated. The updated Managed Build information can no longer be loaded by CDT 2.x. Select No and the project will not be updated. You will be able to view the Managed Build settings, but no changes will be saved when you close the project or exit Eclipse.