[3.12] gh-113602: Bail out when the parser tries to override existing errors (GH-113607) (#113652)

gh-113602: Bail out when the parser tries to override existing errors (GH-113607)
(cherry picked from commit 9ed36d533ab8b256f0a589b5be6d7a2fdcf4aff2)

Signed-off-by: Pablo Galindo <pablogsal@gmail.com>
Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>