rb_econv_make_exception  337 include/ruby/encoding.h VALUE rb_econv_make_exception(rb_econv_t *ec);
rb_econv_make_exception 2278 io.c                   exc = rb_econv_make_exception(fptr->readconv);
rb_econv_make_exception 4120 io.c                           return noalloc ? Qtrue : rb_econv_make_exception(fptr->writeconv);
rb_econv_make_exception 4141 io.c                       return noalloc ? Qtrue : rb_econv_make_exception(fptr->writeconv);