No subject

is a subdir of 'worker' where snd_lib has been defined so it should be
visible, I guess...

unless you define the snd_lib var AFTER you
add_subdirectory(chatterbox)

since add_subdirectory process subdir first you must define
variable you need before "add_subdirectory".

> How to handle this situation in a proper way?

Define it at the scope it ought to be ?
or use
 set (snd_lib "sndlib" PARENT_SCOPE)

but again I think your problems comes from the fact
your defined your var after add_subdirectory.

--=20
Erk
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