https://bugs.gentoo.org/961421
Could be done safely, as this is leaf package, bools don't escape
and aren't used in parsing actual tag frames from the media.
--- a/src/aux_id3lib.c
+++ b/src/aux_id3lib.c
@@ -11,6 +11,7 @@
  */
 
 #include "config.h"
+#include <stdbool.h>
 
 #ifdef LIBID3_MISSING_ID3FRAMEINFO