Fix corner-case 64-bit integer subtraction bug on some platforms.
authorDean Rasheed
Thu, 9 Nov 2023 09:53:05 +0000 (09:53 +0000)
committerDean Rasheed
Thu, 9 Nov 2023 09:53:05 +0000 (09:53 +0000)
commitc396aca2b712f7872dcc4641a2a0fa553f232f76
tree55d944e4fa7bfa450ec1c0b5355d332ee560fa02
parent179c4639cf1dcbe54f3469d7f44a11f172332893
Fix corner-case 64-bit integer subtraction bug on some platforms.

When computing "0 - INT64_MIN", most platforms would report an
overflow error, which is correct. However, platforms without integer
overflow builtins or 128-bit integers would fail to spot the overflow,
and incorrectly return INT64_MIN.

Back-patch to all supported branches.

Patch be me. Thanks to Jian He for initial investigation, and Laurenz
Albe and Tom Lane for review.

Discussion: https://postgr.es/m/CAEZATCUNK-AZSD0jVdgkk0N%3DNcAXBWeAEX-QU9AnJPensikmdQ%40mail.gmail.com
src/include/common/int.h
src/test/regress/expected/int8.out
src/test/regress/sql/int8.sql