In objects.h rev. 1.17 (Jan 14, 2022),

In objects.h rev. 1.17 (Jan 14, 2022),
tb@ removed the following macros from the public API:
_DECLARE_OBJ_BSEARCH_CMP_FN
DECLARE_OBJ_BSEARCH_CMP_FN DECLARE_OBJ_BSEARCH_GLOBAL_CMP_FN
IMPLEMENT_OBJ_BSEARCH_CMP_FN IMPLEMENT_OBJ_BSEARCH_GLOBAL_CMP_FN
OBJ_bsearch OBJ_bsearch_ex

In objects.h rev. 1.20 (Nov 11, 2022), jsing@ unifdef'ed USE_OBJ_MAC.

Stop marking these names as intentionally undocumented.