backtraces_string  595 gc/misc.c              char * backtraces_string = GETENV("GC_BACKTRACES");
backtraces_string  596 gc/misc.c              if (0 != backtraces_string) {
backtraces_string  597 gc/misc.c                GC_backtraces = atol(backtraces_string);
backtraces_string  598 gc/misc.c      	  if (backtraces_string[0] == '\0') GC_backtraces = 1;