diff --git a/src/lib-sieve/sieve-validator.c b/src/lib-sieve/sieve-validator.c
index 4599de460588f1b967bcbce5f48f5febd02255e9..5984d9126657a47c30ecf13b2b9ecad465227edd 100644
--- a/src/lib-sieve/sieve-validator.c
+++ b/src/lib-sieve/sieve-validator.c
@@ -29,7 +29,6 @@ struct sieve_validator {
 
 static void sieve_validator_register_core_commands(struct sieve_validator *validator);
 static void sieve_validator_register_core_tests(struct sieve_validator *validator);
-static void sieve_validator_register_core_comparators(struct sieve_validator *validator);
 
 /* Error management */