[adrian_b]

When the project is so big that this is a problem, you can make an additional make target, e.g. "make file_lists" that would use globbing and store the lists into a file that will be used by any other make commands.

The bigger a project is, the more important is to use only globbing and never write explicitly any file name lists.

However, I believe that this, the slowness of globbing for big directories, might be a strictly Windows-specific problem, if it exists. At least on Linux and with XFS (which has B-tree directories) I have never seen globbing to take any noticeable time, even on directories with ten thousand files or more, where it still appears to be instantaneous at the human reaction time scale.

There is no reason to ever do recursive scans. All the directories with source files of a project must be scanned to search for any source files located there, but only once.