Alvaro Herrera <alvherre@commandprompt.com> writes:
> Bruce Momjian wrote:
>> The problem is having a function's output affected by a GUC variable.
> Mark the function as volatile, which precludes from using it in a
> functional index?
Stable, not volatile.
It looks like we have some of the variants marked stable already for
their dependence on TimeZone, but the dependence on lc_messages is new.
regards, tom lane