[33/38] Compiling C object 'app/a172ced@@test_queue@exe/tests_test_queue.c.o'.
FAILED: app/a172ced@@test_queue@exe/tests_test_queue.c.o
/nix/store/4yhnj6g8ixx31jgil477xrir5y3n39im-clang-wrapper-7.1.0/bin/cc -Iapp/a172ced@@test_queue@exe -Iapp -I../app -I../app/src -I/nix/store/gl5yaaflmwpap4sxnbjjck243lpzcpys-ffmpeg-3.4.6-dev/include -I/nix/store/0pn4dchsfz57xi5b3dnwci44krnd53g2-SDL2-2.0.9-dev/include/SDL2 -Xclang -fcolor-diagnostics -pipe -std=c11 -D_THREAD_SAFE -MD -MQ 'app/a172ced@@test_queue@exe/tests_test_queue.c.o' -MF 'app/a172ced@@test_queue@exe/tests_test_queue.c.o.d' -o 'app/a172ced@@test_queue@exe/tests_test_queue.c.o' -c ../app/tests/test_queue.c
../app/tests/test_queue.c:12:5: error: use of undeclared identifier 'NULL'
    queue_init(&queue);
    ^
../app/src/queue.h:16:40: note: expanded from macro 'queue_init'
    (void) ((PQ)->first = (PQ)->last = NULL)
                                       ^
../app/tests/test_queue.c:19:5: error: use of undeclared identifier 'NULL'
    queue_push(&queue, next, &v1);
    ^
../app/src/queue.h:52:29: note: expanded from macro 'queue_push'
        (ITEM)->NEXTFIELD = NULL; \
                            ^
../app/tests/test_queue.c:20:5: error: use of undeclared identifier 'NULL'
    queue_push(&queue, next, &v2);
    ^
../app/src/queue.h:52:29: note: expanded from macro 'queue_push'
        (ITEM)->NEXTFIELD = NULL; \
                            ^
3 errors generated.
ninja: build stopped: subcommand failed.