title: Why is "Build Project" greyed-out in Eclipse Helios CDT even though the makefile and source exist?
body: <p>I can't build my project.</p>
  
  <p>I created a new CDT project in Eclipse Helios and told it to use existing source and makefile -- both, of which, appear correctly in the Package and Project views. The "Project" menu has both "Build All" and "Build Project" grayed-out, however, so it's impossible to build the project. "Build Automatically" is unchecked. During project creation, I told the wizard to use the Linux gcc(1) toolchain. I've been unable to find anything under Project->Properties or Window->Preferences that enables the "Build Project" feature. The Window->Preferences->Build display shows only one tab labeled "Error Parsers".</p>
  
  <p>How can I enable the "Build Project" command?</p>