diff --git a/coccinelle/not_in_set.cocci b/coccinelle/not_in_set.cocci
new file mode 100644
index 0000000000..e6bcf47893
--- /dev/null
+++ b/coccinelle/not_in_set.cocci
@@ -0,0 +1,147 @@
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16, n17, n18, n19, n20;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11 && e != n12 && e != n13 && e != n14 && e != n15 && e != n16 && e != n17 && e != n18 && e != n19 && e != n20
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16, n17, n18, n19, n20)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16, n17, n18, n19;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11 && e != n12 && e != n13 && e != n14 && e != n15 && e != n16 && e != n17 && e != n18 && e != n19
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16, n17, n18, n19)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16, n17, n18;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11 && e != n12 && e != n13 && e != n14 && e != n15 && e != n16 && e != n17 && e != n18
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16, n17, n18)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16, n17;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11 && e != n12 && e != n13 && e != n14 && e != n15 && e != n16 && e != n17
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16, n17)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11 && e != n12 && e != n13 && e != n14 && e != n15 && e != n16
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15, n16)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11 && e != n12 && e != n13 && e != n14 && e != n15
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14, n15)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11 && e != n12 && e != n13 && e != n14
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13, n14)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11 && e != n12 && e != n13
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12, n13)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11 && e != n12
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11, n12)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10 && e != n11
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9 && e != n10
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8, n9;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8 && e != n9
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7, n8;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7 && e != n8
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7, n8)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6, n7;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6 && e != n7
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6, n7)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5, n6;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5 && e != n6
++ !IN_SET(e, n0, n1, n2, n3, n4, n5, n6)
+@@
+expression e;
+identifier n0, n1, n2, n3, n4, n5;
+statement s;
+@@
+- e != n0 && e != n1 && e != n2 && e != n3 && e != n4 && e != n5
++ !IN_SET(e, n0, n1, n2, n3, n4, n5)
+@@
+expression e;
+identifier n1, n2, n3, n4, n5;
+statement s;
+@@
+- e != n1 && e != n2 && e != n3 && e != n4 && e != n5
++ !IN_SET(e, n1, n2, n3, n4, n5)
+@@
+expression e;
+identifier n1, n2, n3, n4;
+statement s;
+@@
+- e != n1 && e != n2 && e != n3 && e != n4
++ !IN_SET(e, n1, n2, n3, n4)
+@@
+expression e;
+identifier n1, n2, n3, n4;
+statement s;
+@@
+- e != n1 && e != n2 && e != n3 && e != n4
++ !IN_SET(e, n1, n2, n3, n4)
+@@
+expression e;
+identifier n1, n2, n3;
+statement s;
+@@
+- e != n1 && e != n2 && e != n3
++ !IN_SET(e, n1, n2, n3)
+@@
+expression e;
+identifier n, p;
+statement s;
+@@
+- e != n && e != p
++ !IN_SET(e, n, p)
diff --git a/src/basic/rm-rf.c b/src/basic/rm-rf.c
index 3f80ed263a..77fe88e42c 100644
--- a/src/basic/rm-rf.c
+++ b/src/basic/rm-rf.c
@@ -202,7 +202,7 @@ int rm_rf(const char *path, RemoveFlags flags) {
         fd = open(path, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME);
         if (fd < 0) {
 
-                if (errno != ENOTDIR && errno != ELOOP)
+                if (!IN_SET(errno, ENOTDIR, ELOOP))
                         return -errno;
 
                 if (!(flags & REMOVE_PHYSICAL)) {
diff --git a/src/basic/socket-util.c b/src/basic/socket-util.c
index c2f795b4d8..e8d39674cc 100644
--- a/src/basic/socket-util.c
+++ b/src/basic/socket-util.c
@@ -268,7 +268,7 @@ int socket_address_verify(const SocketAddress *a) {
                 if (a->sockaddr.in.sin_port == 0)
                         return -EINVAL;
 
-                if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
+                if (!IN_SET(a->type, SOCK_STREAM, SOCK_DGRAM))
                         return -EINVAL;
 
                 return 0;
@@ -280,7 +280,7 @@ int socket_address_verify(const SocketAddress *a) {
                 if (a->sockaddr.in6.sin6_port == 0)
                         return -EINVAL;
 
-                if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
+                if (!IN_SET(a->type, SOCK_STREAM, SOCK_DGRAM))
                         return -EINVAL;
 
                 return 0;
@@ -304,7 +304,7 @@ int socket_address_verify(const SocketAddress *a) {
                         }
                 }
 
-                if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM && a->type != SOCK_SEQPACKET)
+                if (!IN_SET(a->type, SOCK_STREAM, SOCK_DGRAM, SOCK_SEQPACKET))
                         return -EINVAL;
 
                 return 0;
@@ -314,7 +314,7 @@ int socket_address_verify(const SocketAddress *a) {
                 if (a->size != sizeof(struct sockaddr_nl))
                         return -EINVAL;
 
-                if (a->type != SOCK_RAW && a->type != SOCK_DGRAM)
+                if (!IN_SET(a->type, SOCK_RAW, SOCK_DGRAM))
                         return -EINVAL;
 
                 return 0;
@@ -323,7 +323,7 @@ int socket_address_verify(const SocketAddress *a) {
                 if (a->size != sizeof(struct sockaddr_vm))
                         return -EINVAL;
 
-                if (a->type != SOCK_STREAM && a->type != SOCK_DGRAM)
+                if (!IN_SET(a->type, SOCK_STREAM, SOCK_DGRAM))
                         return -EINVAL;
 
                 return 0;
diff --git a/src/core/audit-fd.c b/src/core/audit-fd.c
index a91906b626..bc421a4343 100644
--- a/src/core/audit-fd.c
+++ b/src/core/audit-fd.c
@@ -48,7 +48,7 @@ int get_audit_fd(void) {
                 audit_fd = audit_open();
 
                 if (audit_fd < 0) {
-                        if (errno != EAFNOSUPPORT && errno != EPROTONOSUPPORT)
+                        if (!IN_SET(errno, EAFNOSUPPORT, EPROTONOSUPPORT))
                                 log_error_errno(errno, "Failed to connect to audit log: %m");
 
                         audit_fd = errno ? -errno : -EINVAL;
diff --git a/src/core/automount.c b/src/core/automount.c
index ecaa916ce3..9b0d1ca429 100644
--- a/src/core/automount.c
+++ b/src/core/automount.c
@@ -251,8 +251,7 @@ static void automount_set_state(Automount *a, AutomountState state) {
         if (state != AUTOMOUNT_RUNNING)
                 automount_stop_expire(a);
 
-        if (state != AUTOMOUNT_WAITING &&
-            state != AUTOMOUNT_RUNNING)
+        if (!IN_SET(state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING))
                 unmount_autofs(a);
 
         if (state != old_state)
diff --git a/src/core/killall.c b/src/core/killall.c
index 3fe9fa2ed0..5e914e478d 100644
--- a/src/core/killall.c
+++ b/src/core/killall.c
@@ -174,8 +174,7 @@ static int killall(int sig, Set *pids, bool send_sighup) {
                 pid_t pid;
                 int r;
 
-                if (d->d_type != DT_DIR &&
-                    d->d_type != DT_UNKNOWN)
+                if (!IN_SET(d->d_type, DT_DIR, DT_UNKNOWN))
                         continue;
 
                 if (parse_pid(d->d_name, &pid) < 0)
diff --git a/src/core/manager.c b/src/core/manager.c
index 519473599a..da673c7ae2 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -2513,9 +2513,7 @@ void manager_send_unit_plymouth(Manager *m, Unit *u) {
         if (detect_container() > 0)
                 return;
 
-        if (u->type != UNIT_SERVICE &&
-            u->type != UNIT_MOUNT &&
-            u->type != UNIT_SWAP)
+        if (!IN_SET(u->type, UNIT_SERVICE, UNIT_MOUNT, UNIT_SWAP))
                 return;
 
         /* We set SOCK_NONBLOCK here so that we rather drop the
diff --git a/src/core/path.c b/src/core/path.c
index bbf891c462..44831f5803 100644
--- a/src/core/path.c
+++ b/src/core/path.c
@@ -669,8 +669,7 @@ static int path_dispatch_io(sd_event_source *source, int fd, uint32_t revents, v
 
         p = PATH(s->unit);
 
-        if (p->state != PATH_WAITING &&
-            p->state != PATH_RUNNING)
+        if (!IN_SET(p->state, PATH_WAITING, PATH_RUNNING))
                 return 0;
 
         /* log_debug("inotify wakeup on %s.", u->id); */
diff --git a/src/core/socket.c b/src/core/socket.c
index d579f341fb..06ceb46eca 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -2055,7 +2055,7 @@ static void socket_enter_signal(Socket *s, SocketState state, SocketResult f) {
         r = unit_kill_context(
                         UNIT(s),
                         &s->kill_context,
-                        (state != SOCKET_STOP_PRE_SIGTERM && state != SOCKET_FINAL_SIGTERM) ?
+                        !IN_SET(state, SOCKET_STOP_PRE_SIGTERM, SOCKET_FINAL_SIGTERM) ?
                         KILL_KILL : KILL_TERMINATE,
                         -1,
                         s->control_pid,
@@ -2448,9 +2448,7 @@ static int socket_start(Unit *u) {
 
                 /* If the service is already active we cannot start the
                  * socket */
-                if (service->state != SERVICE_DEAD &&
-                    service->state != SERVICE_FAILED &&
-                    service->state != SERVICE_AUTO_RESTART) {
+                if (!IN_SET(service->state, SERVICE_DEAD, SERVICE_FAILED, SERVICE_AUTO_RESTART)) {
                         log_unit_error(u, "Socket service %s already active, refusing.", UNIT(service)->id);
                         return -EBUSY;
                 }
diff --git a/src/core/unit.c b/src/core/unit.c
index 0ef6fcfab5..90112a8b15 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -778,8 +778,7 @@ int unit_merge(Unit *u, Unit *other) {
         if (!unit_type_may_alias(u->type)) /* Merging only applies to unit names that support aliases */
                 return -EEXIST;
 
-        if (other->load_state != UNIT_STUB &&
-            other->load_state != UNIT_NOT_FOUND)
+        if (!IN_SET(other->load_state, UNIT_STUB, UNIT_NOT_FOUND))
                 return -EEXIST;
 
         if (other->job)
@@ -2221,7 +2220,7 @@ void unit_notify(Unit *u, UnitActiveState os, UnitActiveState ns, bool reload_su
                         if (u->job->state == JOB_RUNNING) {
                                 if (ns == UNIT_ACTIVE)
                                         job_finish_and_invalidate(u->job, reload_success ? JOB_DONE : JOB_FAILED, true, false);
-                                else if (ns != UNIT_ACTIVATING && ns != UNIT_RELOADING) {
+                                else if (!IN_SET(ns, UNIT_ACTIVATING, UNIT_RELOADING)) {
                                         unexpected = true;
 
                                         if (UNIT_IS_INACTIVE_OR_FAILED(ns))
diff --git a/src/import/import-compress.c b/src/import/import-compress.c
index f1766bbe3b..01b78fc9a6 100644
--- a/src/import/import-compress.c
+++ b/src/import/import-compress.c
@@ -135,7 +135,7 @@ int import_uncompress(ImportCompress *c, const void *data, size_t size, ImportCo
                         c->xz.avail_out = sizeof(buffer);
 
                         lzr = lzma_code(&c->xz, LZMA_RUN);
-                        if (lzr != LZMA_OK && lzr != LZMA_STREAM_END)
+                        if (!IN_SET(lzr, LZMA_OK, LZMA_STREAM_END))
                                 return -EIO;
 
                         r = callback(buffer, sizeof(buffer) - c->xz.avail_out, userdata);
@@ -156,7 +156,7 @@ int import_uncompress(ImportCompress *c, const void *data, size_t size, ImportCo
                         c->gzip.avail_out = sizeof(buffer);
 
                         r = inflate(&c->gzip, Z_NO_FLUSH);
-                        if (r != Z_OK && r != Z_STREAM_END)
+                        if (!IN_SET(r, Z_OK, Z_STREAM_END))
                                 return -EIO;
 
                         r = callback(buffer, sizeof(buffer) - c->gzip.avail_out, userdata);
@@ -177,7 +177,7 @@ int import_uncompress(ImportCompress *c, const void *data, size_t size, ImportCo
                         c->bzip2.avail_out = sizeof(buffer);
 
                         r = BZ2_bzDecompress(&c->bzip2);
-                        if (r != BZ_OK && r != BZ_STREAM_END)
+                        if (!IN_SET(r, BZ_OK, BZ_STREAM_END))
                                 return -EIO;
 
                         r = callback(buffer, sizeof(buffer) - c->bzip2.avail_out, userdata);
@@ -399,7 +399,7 @@ int import_compress_finish(ImportCompress *c, void **buffer, size_t *buffer_size
                         c->xz.avail_out = *buffer_allocated - *buffer_size;
 
                         lzr = lzma_code(&c->xz, LZMA_FINISH);
-                        if (lzr != LZMA_OK && lzr != LZMA_STREAM_END)
+                        if (!IN_SET(lzr, LZMA_OK, LZMA_STREAM_END))
                                 return -EIO;
 
                         *buffer_size += (*buffer_allocated - *buffer_size) - c->xz.avail_out;
@@ -420,7 +420,7 @@ int import_compress_finish(ImportCompress *c, void **buffer, size_t *buffer_size
                         c->gzip.avail_out = *buffer_allocated - *buffer_size;
 
                         r = deflate(&c->gzip, Z_FINISH);
-                        if (r != Z_OK && r != Z_STREAM_END)
+                        if (!IN_SET(r, Z_OK, Z_STREAM_END))
                                 return -EIO;
 
                         *buffer_size += (*buffer_allocated - *buffer_size) - c->gzip.avail_out;
@@ -440,7 +440,7 @@ int import_compress_finish(ImportCompress *c, void **buffer, size_t *buffer_size
                         c->bzip2.avail_out = *buffer_allocated - *buffer_size;
 
                         r = BZ2_bzCompress(&c->bzip2, BZ_FINISH);
-                        if (r != BZ_FINISH_OK && r != BZ_STREAM_END)
+                        if (!IN_SET(r, BZ_FINISH_OK, BZ_STREAM_END))
                                 return -EIO;
 
                         *buffer_size += (*buffer_allocated - *buffer_size) - c->bzip2.avail_out;
diff --git a/src/import/importd.c b/src/import/importd.c
index bdb9910010..e20aca0d9e 100644
--- a/src/import/importd.c
+++ b/src/import/importd.c
@@ -417,7 +417,7 @@ static int transfer_start(Transfer *t) {
                         }
                 }
 
-                if (pipefd[1] != STDOUT_FILENO && pipefd[1] != STDERR_FILENO)
+                if (!IN_SET(pipefd[1], STDOUT_FILENO, STDERR_FILENO))
                         pipefd[1] = safe_close(pipefd[1]);
 
                 if (t->stdin_fd >= 0) {
diff --git a/src/journal/journal-file.c b/src/journal/journal-file.c
index 94f0559d64..ec66f4d5a4 100644
--- a/src/journal/journal-file.c
+++ b/src/journal/journal-file.c
@@ -1650,8 +1650,7 @@ uint64_t journal_file_entry_array_n_items(Object *o) {
 uint64_t journal_file_hash_table_n_items(Object *o) {
         assert(o);
 
-        if (o->object.type != OBJECT_DATA_HASH_TABLE &&
-            o->object.type != OBJECT_FIELD_HASH_TABLE)
+        if (!IN_SET(o->object.type, OBJECT_DATA_HASH_TABLE, OBJECT_FIELD_HASH_TABLE))
                 return 0;
 
         return (le64toh(o->object.size) - offsetof(Object, hash_table.items)) / sizeof(HashItem);
@@ -3241,8 +3240,7 @@ int journal_file_open(
         assert(ret);
         assert(fd >= 0 || fname);
 
-        if ((flags & O_ACCMODE) != O_RDONLY &&
-            (flags & O_ACCMODE) != O_RDWR)
+        if (!IN_SET((flags & O_ACCMODE), O_RDONLY, O_RDWR))
                 return -EINVAL;
 
         if (fname) {
diff --git a/src/journal/journal-send.c b/src/journal/journal-send.c
index 5d8b394752..4acef26394 100644
--- a/src/journal/journal-send.c
+++ b/src/journal/journal-send.c
@@ -302,7 +302,7 @@ _public_ int sd_journal_sendv(const struct iovec *iov, int n) {
         if (errno == ENOENT)
                 return 0;
 
-        if (errno != EMSGSIZE && errno != ENOBUFS)
+        if (!IN_SET(errno, EMSGSIZE, ENOBUFS))
                 return -errno;
 
         /* Message doesn't fit... Let's dump the data in a memfd or
diff --git a/src/libsystemd-network/sd-dhcp-client.c b/src/libsystemd-network/sd-dhcp-client.c
index 25cff849e5..d0ce7989d8 100644
--- a/src/libsystemd-network/sd-dhcp-client.c
+++ b/src/libsystemd-network/sd-dhcp-client.c
@@ -455,9 +455,7 @@ int sd_dhcp_client_set_mtu(sd_dhcp_client *client, uint32_t mtu) {
 int sd_dhcp_client_get_lease(sd_dhcp_client *client, sd_dhcp_lease **ret) {
         assert_return(client, -EINVAL);
 
-        if (client->state != DHCP_STATE_BOUND &&
-            client->state != DHCP_STATE_RENEWING &&
-            client->state != DHCP_STATE_REBINDING)
+        if (!IN_SET(client->state, DHCP_STATE_BOUND, DHCP_STATE_RENEWING, DHCP_STATE_REBINDING))
                 return -EADDRNOTAVAIL;
 
         if (ret)
diff --git a/src/login/logind-user.c b/src/login/logind-user.c
index 66d9d06b5f..d2e5c74fab 100644
--- a/src/login/logind-user.c
+++ b/src/login/logind-user.c
@@ -354,7 +354,7 @@ static int user_mkdir_runtime_path(User *u) {
 
                 r = mount("tmpfs", u->runtime_path, "tmpfs", MS_NODEV|MS_NOSUID, t);
                 if (r < 0) {
-                        if (errno != EPERM && errno != EACCES) {
+                        if (!IN_SET(errno, EPERM, EACCES)) {
                                 r = log_error_errno(errno, "Failed to mount per-user tmpfs directory %s: %m", u->runtime_path);
                                 goto fail;
                         }
diff --git a/src/network/networkd-network.c b/src/network/networkd-network.c
index 6fd550b80c..a850c0caf4 100644
--- a/src/network/networkd-network.c
+++ b/src/network/networkd-network.c
@@ -749,16 +749,7 @@ int config_parse_tunnel(const char *unit,
                 return 0;
         }
 
-        if (netdev->kind != NETDEV_KIND_IPIP &&
-            netdev->kind != NETDEV_KIND_SIT &&
-            netdev->kind != NETDEV_KIND_GRE &&
-            netdev->kind != NETDEV_KIND_GRETAP &&
-            netdev->kind != NETDEV_KIND_IP6GRE &&
-            netdev->kind != NETDEV_KIND_IP6GRETAP &&
-            netdev->kind != NETDEV_KIND_VTI &&
-            netdev->kind != NETDEV_KIND_VTI6 &&
-            netdev->kind != NETDEV_KIND_IP6TNL
-        ) {
+        if (!IN_SET(netdev->kind, NETDEV_KIND_IPIP, NETDEV_KIND_SIT, NETDEV_KIND_GRE, NETDEV_KIND_GRETAP, NETDEV_KIND_IP6GRE, NETDEV_KIND_IP6GRETAP, NETDEV_KIND_VTI, NETDEV_KIND_VTI6, NETDEV_KIND_IP6TNL)) {
                 log_syntax(unit, LOG_ERR, filename, line, 0,
                            "NetDev is not a tunnel, ignoring assignment: %s", rvalue);
                 return 0;
diff --git a/src/nss-myhostname/nss-myhostname.c b/src/nss-myhostname/nss-myhostname.c
index 1f27e06e6f..96ed161ba7 100644
--- a/src/nss-myhostname/nss-myhostname.c
+++ b/src/nss-myhostname/nss-myhostname.c
@@ -337,7 +337,7 @@ enum nss_status _nss_myhostname_gethostbyname3_r(
         if (af == AF_UNSPEC)
                 af = AF_INET;
 
-        if (af != AF_INET && af != AF_INET6) {
+        if (!IN_SET(af, AF_INET, AF_INET6)) {
                 *errnop = EAFNOSUPPORT;
                 *h_errnop = NO_DATA;
                 return NSS_STATUS_UNAVAIL;
diff --git a/src/resolve/resolved-dns-stream.c b/src/resolve/resolved-dns-stream.c
index 878bae47dc..4a94fa9916 100644
--- a/src/resolve/resolved-dns-stream.c
+++ b/src/resolve/resolved-dns-stream.c
@@ -221,7 +221,7 @@ static int on_stream_io(sd_event_source *es, int fd, uint32_t revents, void *use
 
                 ss = writev(fd, iov, 2);
                 if (ss < 0) {
-                        if (errno != EINTR && errno != EAGAIN)
+                        if (!IN_SET(errno, EINTR, EAGAIN))
                                 return dns_stream_complete(s, errno);
                 } else
                         s->n_written += ss;
@@ -243,7 +243,7 @@ static int on_stream_io(sd_event_source *es, int fd, uint32_t revents, void *use
 
                         ss = read(fd, (uint8_t*) &s->read_size + s->n_read, sizeof(s->read_size) - s->n_read);
                         if (ss < 0) {
-                                if (errno != EINTR && errno != EAGAIN)
+                                if (!IN_SET(errno, EINTR, EAGAIN))
                                         return dns_stream_complete(s, errno);
                         } else if (ss == 0)
                                 return dns_stream_complete(s, ECONNRESET);
@@ -293,7 +293,7 @@ static int on_stream_io(sd_event_source *es, int fd, uint32_t revents, void *use
                                           (uint8_t*) DNS_PACKET_DATA(s->read_packet) + s->n_read - sizeof(s->read_size),
                                           sizeof(s->read_size) + be16toh(s->read_size) - s->n_read);
                                 if (ss < 0) {
-                                        if (errno != EINTR && errno != EAGAIN)
+                                        if (!IN_SET(errno, EINTR, EAGAIN))
                                                 return dns_stream_complete(s, errno);
                                 } else if (ss == 0)
                                         return dns_stream_complete(s, ECONNRESET);
diff --git a/src/socket-proxy/socket-proxyd.c b/src/socket-proxy/socket-proxyd.c
index 1b99b7bc82..bf8c2f86a3 100644
--- a/src/socket-proxy/socket-proxyd.c
+++ b/src/socket-proxy/socket-proxyd.c
@@ -167,7 +167,7 @@ static int connection_shovel(
                         } else if (z == 0 || errno == EPIPE || errno == ECONNRESET) {
                                 *from_source = sd_event_source_unref(*from_source);
                                 *from = safe_close(*from);
-                        } else if (errno != EAGAIN && errno != EINTR)
+                        } else if (!IN_SET(errno, EAGAIN, EINTR))
                                 return log_error_errno(errno, "Failed to splice: %m");
                 }
 
@@ -179,7 +179,7 @@ static int connection_shovel(
                         } else if (z == 0 || errno == EPIPE || errno == ECONNRESET) {
                                 *to_source = sd_event_source_unref(*to_source);
                                 *to = safe_close(*to);
-                        } else if (errno != EAGAIN && errno != EINTR)
+                        } else if (!IN_SET(errno, EAGAIN, EINTR))
                                 return log_error_errno(errno, "Failed to splice: %m");
                 }
         } while (shoveled);
diff --git a/src/test/test-cgroup-util.c b/src/test/test-cgroup-util.c
index 30cd463722..d5bc73feff 100644
--- a/src/test/test-cgroup-util.c
+++ b/src/test/test-cgroup-util.c
@@ -192,8 +192,7 @@ static void test_proc(void) {
                 pid_t pid;
                 uid_t uid = UID_INVALID;
 
-                if (de->d_type != DT_DIR &&
-                    de->d_type != DT_UNKNOWN)
+                if (!IN_SET(de->d_type, DT_DIR, DT_UNKNOWN))
                         continue;
 
                 r = parse_pid(de->d_name, &pid);
diff --git a/src/test/test-execute.c b/src/test/test-execute.c
index a38efc7cba..ea68225ad7 100644
--- a/src/test/test-execute.c
+++ b/src/test/test-execute.c
@@ -54,7 +54,7 @@ static void check(Manager *m, Unit *unit, int status_expected, int code_expected
         printf("%s\n", unit->id);
         exec_context_dump(&service->exec_context, stdout, "\t");
         ts = now(CLOCK_MONOTONIC);
-        while (service->state != SERVICE_DEAD && service->state != SERVICE_FAILED) {
+        while (!IN_SET(service->state, SERVICE_DEAD, SERVICE_FAILED)) {
                 int r;
                 usec_t n;
 
diff --git a/src/udev/mtd_probe/probe_smartmedia.c b/src/udev/mtd_probe/probe_smartmedia.c
index 2a7ba17637..89bceaa146 100644
--- a/src/udev/mtd_probe/probe_smartmedia.c
+++ b/src/udev/mtd_probe/probe_smartmedia.c
@@ -54,7 +54,7 @@ void probe_smart_media(int mtd_fd, mtd_info_t* info)
         block_size = info->erasesize;
         size_in_megs = info->size / (1024 * 1024);
 
-        if (sector_size != SM_SECTOR_SIZE && sector_size != SM_SMALL_PAGE)
+        if (!IN_SET(sector_size, SM_SECTOR_SIZE, SM_SMALL_PAGE))
                 goto exit;
 
         switch(size_in_megs) {
diff --git a/src/udev/udev-builtin-path_id.c b/src/udev/udev-builtin-path_id.c
index 8cb330dba1..f5d7c23d9f 100644
--- a/src/udev/udev-builtin-path_id.c
+++ b/src/udev/udev-builtin-path_id.c
@@ -411,7 +411,7 @@ static struct udev_device *handle_scsi_default(struct udev_device *parent, char
 
                 if (dent->d_name[0] == '.')
                         continue;
-                if (dent->d_type != DT_DIR && dent->d_type != DT_LNK)
+                if (!IN_SET(dent->d_type, DT_DIR, DT_LNK))
                         continue;
                 if (!startswith(dent->d_name, "host"))
                         continue;