Hello Mirek,

It didn't work but I've got a more detailed error -instead of plain nullptr- by using clang_parseTranslationUnit2() function, which returns an enum, defined in CxErrorCode.h):

 /**
  * An AST deserialization error has occurred.
  */
 CXError_ASTReadError = 4

I'll dig deeper, but if this gives you any hints, please let me know.

Best regards,
Oblivion