Instead of adding __attribute__((unused)) to unused arguments, add the
-Wno-unused-parameter compiler flag.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Declare dynamically allocated strings as 'char *' instead of 'const char *'.
Remove the discard_const() macro. Do not test whether or not a pointer is
NULL before calling free() because it is allowed to pass NULL to free().
Signed-off-by: Bart Van Assche <bvanassche@acm.org>