GFORTRAN_ERROR_BACKTRACE (The GNU Fortran Compiler)

### 3.11 `GFORTRAN_ERROR_BACKTRACE`—Show backtrace on run-time errors ¶

If the `GFORTRAN_ERROR_BACKTRACE` variable is set to ‘`y`’, ‘`Y`’ or ‘`1`’ (only the first letter is relevant) then a backtrace is printed when a serious run-time error occurs. To disable the backtracing, set the variable to ‘`n`’, ‘`N`’, ‘`0`’. Default is to print a backtrace unless the `-fno-backtrace` compile option was used.