TTL of a CNAME longer than TTL of corresponding right hand side RRs

[THO]

Hi there,

If I remember correctly, there was a (bug ?) years ago that resulted in
libresolv being confused whenever the TTL of a CNAME is longer than TTL
of RRs the CNAME points to.
If this right ? more details ?

More generally, is there any standard and/or best practice and/or
implementation constraincts that would rule these TTL values, one in
respect to the other ?

quite urgent
TIA