bind v9.16.0 dlz_filesystem_dynamic module build FAILs ?

[PGNet Dev]

building 9.16.0, as usual, on linux/64,



config + make of core are OK



of my two usual module builds,



'dlz_bdbhpt_dynamic' is OK



	cd contrib/dlz/modules/

	cd  ./bdbhpt

	make V=1

	ldd dlz_bdbhpt_dynamic.so

	        linux-vdso.so.1 (0x00007fffa312c000)

	        libdb-4.8.so => /usr/lib64/libdb-4.8.so (0x00007f50edc43000)

	        libc.so.6 => /lib64/libc.so.6 (0x00007f50ed89b000)

	        libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f50ed67d000)

	        /lib64/ld-linux-x86-64.so.2 (0x000056482796b000)



but, currently, dlz_filesystem_dynamic FAILs



	cd ../filesystem

	make V=1



		/usr/bin/gcc-9 -fPIC -g -I../include -c dir.c

		In file included from dir.c:17:

		dir.h:38:1: error: unknown type name ‘isc_result_t’

		   38 | isc_result_t

		      | ^~~~~~~~~~~~

		dir.h:41:1: error: unknown type name ‘isc_result_t’

		   41 | isc_result_t

		      | ^~~~~~~~~~~~

		dir.h:44:1: error: unknown type name ‘isc_result_t’

		   44 | isc_result_t

		      | ^~~~~~~~~~~~

		dir.c:39:1: error: conflicting types for ‘dir_open’

		   39 | dir_open(dir_t *dir, const char *dirname)

		      | ^~~~~~~~

		In file included from dir.c:17:

		dir.h:39:1: note: previous declaration of ‘dir_open’ was here

		   39 | dir_open(dir_t *dir, const char *dirname);

		      | ^~~~~~~~

		dir.c:91:1: error: conflicting types for ‘dir_read’

		   91 | dir_read(dir_t *dir)

		      | ^~~~~~~~

		In file included from dir.c:17:

		dir.h:42:1: note: previous declaration of ‘dir_read’ was here

		   42 | dir_read(dir_t *dir);

		      | ^~~~~~~~

		dir.c:122:1: error: conflicting types for ‘dir_reset’

		  122 | dir_reset(dir_t *dir)

		      | ^~~~~~~~~

		In file included from dir.c:17:

		dir.h:45:1: note: previous declaration of ‘dir_reset’ was here

		   45 | dir_reset(dir_t *dir);

		      | ^~~~~~~~~

		make: *** [Makefile:9: dir.o] Error 1



9.14.11's module builds are both, still OK

I've not found relevant mention in CHANGES, and nothing, yet, in bugs etc.

Known issue? fix/workaround available?