* minor incompatible change: prevent the user from specializing the
new-value argument to SB-MOP:SLOT-VALUE-USING-CLASS. It's
somewhat counter to the intent of the protocol, I (CSR) think, and
additionally it just doesn't work in SBCL as currently
implemented, thanks to optimizations (that are always valid for
the other three SLOT-VALUEish functions, but not for the setter).
* minor incompatible change: prevent the user from specializing the
new-value argument to SB-MOP:SLOT-VALUE-USING-CLASS. It's
somewhat counter to the intent of the protocol, I (CSR) think, and
additionally it just doesn't work in SBCL as currently
implemented, thanks to optimizations (that are always valid for
the other three SLOT-VALUEish functions, but not for the setter).