[CMake] ExternalProject_Add without download of local sources?

[Thomas Wolf]

Hello,

i am wondering if it is possible to have an external project building
from local sources, *without* attemtping to download (in that case,
copy) to a specific location.

My sources of the externals are already in my repository, i do not want
to have them compiled.

I looked around for some while now, but didn't find anything rearding
this topic. Maybe i just missed it.

Setting URL and SOURCE_DIR to the same directory deletes the files...

The 3rdpart project in question is just a normal CMakke project, nothing
fancy.

Regards,
Thomas