The logger call virtual destructor when writting logs #861

Hi,

I encounter a problem when starting my C++ code. The logger caused a segmentation fault. After checking backtrace using gdb, I saw that a simple LOG(INFO) sentence in my code calls the virtual destructor. To this end, Logger::Level will become a very large negative number, which results in a segmentation fault.

I tried to run the code, sometimes it is executed normally and the log entry in my code call the function of Writer (marked as 1 in the above pic.). sometimes it leads to segmentation fault by calling the function ~Writer (marked as 2 in the above pic).

The log entry in my code is as following pic. shows

My C++ project is a multi-thread one. In each thread there exists log entries, and I declare following settings before the entry of main function in main.cpp
"INITIALIZE_EASYLOGGINGPP
#define ELPP_THREAD_SAFE
#define ELPP_QT_LOGGING"

And the settings of config file is:

• GLOBAL:
  FORMAT = "%datetime{%Y-%M-%d %H:%m:%s,%g} %fbase:%line [%level] %msg"
  FILENAME = "../logs/my123.log"
  ENABLED = true
  TO_FILE = true
  TO_STANDARD_OUTPUT = true
  SUBSECOND_PRECISION = 3
  PERFORMANCE_TRACKING = true
  MAX_LOG_FILE_SIZE = 1048576000 ## 100MB - Comment starts with two hashes (##)
  LOG_FLUSH_THRESHOLD = 200 ## Flush after every 100 logs

Can you please indicate what leads to the unexpected segmentation fault based on the information I provide.

Thanks in advance.