Thomas Thai <thomas.t.thai@gmail.com> writes:
> PostgreSQL 18 beta crashes with a segmentation fault when casting strings
> to custom types. The crash occurs specifically in PostgreSQL's type-casting
> system, not in extension code.
The reason you're having a problem is that this is not a valid way to
store a custom type. The representation has to be a single blob of
memory [1], and it has to be represented in a way that lets
type-independent code determine its length. Typically that means
following the varlena-header rules.
regards, tom lane
[1] Well, there is a notion of an "expanded" representation that
doesn't have to be a flat blob. But you're not following the
rules for that either.
