g_logv 0x0000000103a3ed2e
g_log 0x0000000103a3e8e2
Glib::Interface_Class::add_interface(unsigned long) const 0x0000000103989aa8
Gst::XImageSink_Class::init() 0x000000010385642c
Gst::XImageSink::get_type() 0x0000000103856ebe
Gst::wrap_init() 0x0000000103858fe7
Gst::init() 0x0000000103859790
Pipeline::Pipeline() Pipeline.cpp:4
Pipeline::Pipeline() Pipeline.cpp:3
main main.cpp:13
start 0x00007fff71544cc9

Pipeline.cpp:4 is the first line of real code. so the error happens before anything else.