CImg.h is cleared during build process

Since a long time I install G’MIC from GIT on my Gentoo system.
I have been successful until January, 8th, this year.
But now it fails.
In my ebuild file (Gentoo build instructions) I have downloaded the file from which is OK.
But lateron this file is reset to zero length.

What can be the reason?
Many thanks for a hint,