diff --git a/include/proto/sample.h b/include/proto/sample.h
index 3043662d9..db1053771 100644
--- a/include/proto/sample.h
+++ b/include/proto/sample.h
@@ -27,6 +27,7 @@
 #include <types/stick_table.h>
 
 struct sample_expr *sample_parse_expr(char **str, int *idx, char *err, int err_size, struct arg_list *al);
+struct sample_conv *find_sample_conv(const char *kw, int len);
 struct sample *sample_process(struct proxy *px, struct session *l4,
                                void *l7, unsigned int dir, struct sample_expr *expr,
                                struct sample *p);