Turkish has two different suffixes for relative clauses. The difference is due to the subjectivity in relative clause. In other words; if it defines a subjective, it is constructed with the suffix -En; if not, it is constructed with -DIK/AcAK. (-DIK and -AcAk make time difference in the structure and they cooccur in other structures such as nominalizer.)
(1) Kitap okuyan kızı gördüm. book read-part. girl-acc. see-past-1stp. "I saw the girl who read a book." (2) Kızın okuduğu kitabı gördüm. girl-gen. read-part. book-poss. see-past-1stp. "I saw the book which the girl is reading." (3) Kızın okuyacağı kitabı gördüm. girl-gent. read-part. book-poss. see-past-1stp. "I saw the book which the girl will read."
In these sentences, the change in the suffixes create ungrammaticality. However, there are also structures allow the both structure even though it should be nonsubjective suffix.
(4) Bacasından dumanın çıktığı evi gördüm. chimney-poss.-abl. smog-gen. came out-part. house-acc. see-past-1stp. "I saw the house from whose chimney the smog came out." (5) Bacasından duman çıkan evi gördüm. chimney-gen.-abl. smog come out-part. house-acc. see-past-1stp. "I saw the house from whose chimney the smog came out."
It does not actually define the subject of relative clause but it can form by both suffixes. Furthermore, when I asked it to the native speakers, most of them pointed that the structure with subjective suffix sounds more natural. Do you have any suggestion or reference why or how it can be possible?