Commit 1e493158d3 changed the MATCH_LOWER implementation of GETCHAR()
from SB_lower_char() to use pg_ascii_tolower(). The latter returns an
unsigned char; but the local variable in C_IMatchText was a char.
For single-byte encodings and the C locale, that could lead to a
broken signed/unsigned comparison. For example, the pattern
U&'%\00C6' would never match.
Fix by casting the result of pg_ascii_tolower() explicitly to char.
Reported-by: Greg Burd <greg@burd.me>
Reviewed-by: Greg Burd <greg@burd.me>
Discussion: https://postgr.es/m/_GW2V-rd0QW4BTguAJriA9XVmjOn2mR3-YeAZr9ZU6EtlLvYPEm_r_fV5wGKzSNMzboj_nqn3fk72AYAvOKzEnPlCCHteaYrgESrIhPg6l8=@burd.me
Backpatch-through: 19
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
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