Why does qDebug modify values if I stream in it a value from a pointer?

I have a problem with qDebug. When i try to log some value from a pointer it changes the value of my pointers.

I try to be more specific.

This is part of my code:

def_pipelines_laser->pipelines[0]->param_laser[0]->erosion = erosion;
  def_pipelines_laser->pipelines[0]->param_laser[0]->planarity = CS_nominal/1000;
  def_pipelines_laser->pipelines[0]->param_laser[0]->tolerance_minor = (CS_nominal/1000) - toll_cs;
  def_pipelines_laser->pipelines[0]->param_laser[0]->tolerance_major = (CS_nominal/1000) + toll_cs;
  
  qDebug() << "Laser Data " << def_pipelines_laser->pipelines[0]->param_laser[0]->erosion 
      << " " << def_pipelines_laser->pipelines[0]->param_laser[0]->planarity 
      << " " << def_pipelines_laser->pipelines[0]->param_laser[0]->tolerance_minor 
      << " " << def_pipelines_laser->pipelines[0]->param_laser[0]->tolerance_major;

def_pipeline_laser is a "ParameterT" struct from FlatBuffer

struct ParametersT : public flatbuffers::NativeTable {
  typedef Parameters TableType;
  std::vector<std::unique_ptr<SmartDevice::Station::PipelineT>> pipelines{};
};

erosion and CS_nominal are two simple float which i assign to another flow parameter.

when i do the assignation everything is working fine, as soon as i hit the qdebug the values from my pointer (erosion, planarity, tolerance_minor, tolerance_major) they change to a value close to 0.

if I remove the qdebug or if I use the qdebug in this way everything works fine:

qDebug("Erosion = %s", std::to_string(def_pipelines_laser->pipelines[0]->param_laser[0]->erosion).c_str());
  qDebug("Planarity = %s", std::to_string(def_pipelines_laser->pipelines[0]->param_laser[0]->planarity).c_str());
  qDebug("Tolerance Min = %s", std::to_string(def_pipelines_laser->pipelines[0]->param_laser[0]->tolerance_minor).c_str());
  qDebug("Tolerance Maj = %s", std::to_string(def_pipelines_laser->pipelines[0]->param_laser[0]->tolerance_major).c_str());

i add also two pictures from the debug to let you understand my problem

values before qDebug

values after qDebug

Can someone explain me why?