BUG #18247: Integer overflow leads to negative width

The following bug has been logged on the website:

Bug reference: 18247
Logged by: RekGRpth
Email address: rekgrpth(at)gmail(dot)com
PostgreSQL version: 16.1
Operating system: docker alpine
Description:

CREATE TABLE t (
c01 character(10485760),
c02 character(10485760),
c03 character(10485760),
c04 character(10485760),
c05 character(10485760),
c06 character(10485760),
c07 character(10485760),
c08 character(10485760),
c09 character(10485760),
c10 character(10485760),
c11 character(10485760),
c12 character(10485760),
c13 character(10485760),
c14 character(10485760),
c15 character(10485760),
c16 character(10485760),
c17 character(10485760),
c18 character(10485760),
c19 character(10485760),
c20 character(10485760),
c21 character(10485760),
c22 character(10485760),
c23 character(10485760),
c24 character(10485760),
c25 character(10485760),
c26 character(10485760),
c27 character(10485760),
c28 character(10485760),
c29 character(10485760),
c30 character(10485760),
c31 character(10485760),
c32 character(10485760),
c33 character(10485760),
c34 character(10485760),
c35 character(10485760),
c36 character(10485760),
c37 character(10485760),
c38 character(10485760),
c39 character(10485760),
c40 character(10485760),
c41 character(10485760),
c42 character(10485760),
c43 character(10485760),
c44 character(10485760),
c45 character(10485760),
c46 character(10485760),
c47 character(10485760),
c48 character(10485760),
c49 character(10485760),
c50 character(10485760),
c51 character(10485760),
c52 character(10485760)
);
EXPLAIN SELECT * FROM t;
QUERY PLAN
------------------------------------------------------------
Seq Scan on t (cost=0.00..10.00 rows=1 width=-2113929008)
(1 row)