diff --git a/src/analyze/analyze-security.c b/src/analyze/analyze-security.c
index 1fcdbf9cd3..5408cfdeaa 100644
--- a/src/analyze/analyze-security.c
+++ b/src/analyze/analyze-security.c
@@ -2726,8 +2726,7 @@ static int offline_security_checks(
                 k = verify_prepare_filename(*filename, &prepared);
                 if (k < 0) {
                         log_warning_errno(k, "Failed to prepare filename %s: %m", *filename);
-                        if (r == 0)
-                                r = k;
+                        RET_GATHER(r, k);
                         continue;
                 }
 
@@ -2760,19 +2759,15 @@ static int offline_security_checks(
 
                 k = manager_load_startable_unit_or_warn(m, NULL, prepared, &units[count]);
                 if (k < 0) {
-                        if (r == 0)
-                                r = k;
+                        RET_GATHER(r, k);
                         continue;
                 }
 
                 count++;
         }
 
-        for (size_t i = 0; i < count; i++) {
-                k = offline_security_check(units[i], threshold, policy, pager_flags, json_format_flags);
-                if (k < 0 && r == 0)
-                        r = k;
-        }
+        for (size_t i = 0; i < count; i++)
+                RET_GATHER(r, offline_security_check(units[i], threshold, policy, pager_flags, json_format_flags));
 
         return r;
 }
diff --git a/src/analyze/analyze-verify-util.c b/src/analyze/analyze-verify-util.c
index 132a84649b..ae4164d053 100644
--- a/src/analyze/analyze-verify-util.c
+++ b/src/analyze/analyze-verify-util.c
@@ -157,32 +157,23 @@ int verify_executable(Unit *u, const ExecCommand *exec, const char *root) {
 }
 
 static int verify_executables(Unit *u, const char *root) {
-        ExecCommand *exec;
-        int r = 0, k;
-        unsigned i;
+        int r = 0;
 
         assert(u);
 
-        exec =  u->type == UNIT_SOCKET ? SOCKET(u)->control_command :
+        ExecCommand *exec =
+                u->type == UNIT_SOCKET ? SOCKET(u)->control_command :
                 u->type == UNIT_MOUNT ? MOUNT(u)->control_command :
                 u->type == UNIT_SWAP ? SWAP(u)->control_command : NULL;
-        k = verify_executable(u, exec, root);
-        if (k < 0 && r == 0)
-                r = k;
+        RET_GATHER(r, verify_executable(u, exec, root));
 
         if (u->type == UNIT_SERVICE)
-                for (i = 0; i < ELEMENTSOF(SERVICE(u)->exec_command); i++) {
-                        k = verify_executable(u, SERVICE(u)->exec_command[i], root);
-                        if (k < 0 && r == 0)
-                                r = k;
-                }
+                for (unsigned i = 0; i < ELEMENTSOF(SERVICE(u)->exec_command); i++)
+                        RET_GATHER(r, verify_executable(u, SERVICE(u)->exec_command[i], root));
 
         if (u->type == UNIT_SOCKET)
-                for (i = 0; i < ELEMENTSOF(SOCKET(u)->exec_command); i++) {
-                        k = verify_executable(u, SOCKET(u)->exec_command[i], root);
-                        if (k < 0 && r == 0)
-                                r = k;
-                }
+                for (unsigned i = 0; i < ELEMENTSOF(SOCKET(u)->exec_command); i++)
+                        RET_GATHER(r, verify_executable(u, SOCKET(u)->exec_command[i], root));
 
         return r;
 }
@@ -215,7 +206,7 @@ static int verify_documentation(Unit *u, bool check_man) {
 
 static int verify_unit(Unit *u, bool check_man, const char *root) {
         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
-        int r, k;
+        int r;
 
         assert(u);
 
@@ -227,17 +218,9 @@ static int verify_unit(Unit *u, bool check_man, const char *root) {
         if (r < 0)
                 log_unit_error_errno(u, r, "Failed to create %s/start: %s", u->id, bus_error_message(&error, r));
 
-        k = verify_socket(u);
-        if (k < 0 && r == 0)
-                r = k;
-
-        k = verify_executables(u, root);
-        if (k < 0 && r == 0)
-                r = k;
-
-        k = verify_documentation(u, check_man);
-        if (k < 0 && r == 0)
-                r = k;
+        RET_GATHER(r, verify_socket(u));
+        RET_GATHER(r, verify_executables(u, root));
+        RET_GATHER(r, verify_documentation(u, check_man));
 
         return r;
 }
@@ -267,7 +250,7 @@ int verify_units(
         _unused_ _cleanup_(clear_log_syntax_callback) dummy_t dummy;
         Unit *units[strv_length(filenames)];
         _cleanup_free_ char *var = NULL;
-        int r, k, i, count = 0;
+        int r, k, count = 0;
 
         if (strv_isempty(filenames))
                 return 0;
@@ -306,26 +289,21 @@ int verify_units(
                 k = verify_prepare_filename(*filename, &prepared);
                 if (k < 0) {
                         log_error_errno(k, "Failed to prepare filename %s: %m", *filename);
-                        if (r == 0)
-                                r = k;
+                        RET_GATHER(r, k);
                         continue;
                 }
 
                 k = manager_load_startable_unit_or_warn(m, NULL, prepared, &units[count]);
                 if (k < 0) {
-                        if (r == 0)
-                                r = k;
+                        RET_GATHER(r, k);
                         continue;
                 }
 
                 count++;
         }
 
-        for (i = 0; i < count; i++) {
-                k = verify_unit(units[i], check_man, root);
-                if (k < 0 && r == 0)
-                        r = k;
-        }
+        for (int i = 0; i < count; i++)
+                RET_GATHER(r, verify_unit(units[i], check_man, root));
 
         if (s == POINTER_MAX)
                 return log_oom();
diff --git a/src/basic/errno-util.h b/src/basic/errno-util.h
index 091f99c590..f477db7852 100644
--- a/src/basic/errno-util.h
+++ b/src/basic/errno-util.h
@@ -73,6 +73,16 @@ static inline int RET_NERRNO(int ret) {
         return ret;
 }
 
+/* Collect possible errors in <acc>, so that the first error can be returned.
+ * Returns (possibly updated) <acc>. */
+#define RET_GATHER(acc, err)                    \
+        ({                                      \
+                int *__a = &(acc), __e = (err); \
+                if (*__a >= 0 && __e < 0)       \
+                        *__a = __e;             \
+                *__a;                           \
+        })
+
 static inline int errno_or_else(int fallback) {
         /* To be used when invoking library calls where errno handling is not defined clearly: we return
          * errno if it is set, and the specified error otherwise. The idea is that the caller initializes
diff --git a/src/binfmt/binfmt.c b/src/binfmt/binfmt.c
index e1ddf97914..675ae185e2 100644
--- a/src/binfmt/binfmt.c
+++ b/src/binfmt/binfmt.c
@@ -100,9 +100,7 @@ static int apply_file(const char *filename, bool ignore_enoent) {
                 if (strchr(COMMENTS, p[0]))
                         continue;
 
-                k = apply_rule(filename, line, p);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, apply_rule(filename, line, p));
         }
 
         return r;
@@ -201,7 +199,7 @@ static int binfmt_mounted_warn(void) {
 }
 
 static int run(int argc, char *argv[]) {
-        int r, k;
+        int r;
 
         r = parse_argv(argc, argv);
         if (r <= 0)
@@ -221,11 +219,9 @@ static int run(int argc, char *argv[]) {
                 if (r <= 0)
                         return r;
 
-                for (int i = optind; i < argc; i++) {
-                        k = apply_file(argv[i], false);
-                        if (k < 0 && r >= 0)
-                                r = k;
-                }
+                for (int i = optind; i < argc; i++)
+                        RET_GATHER(r, apply_file(argv[i], false));
+
         } else {
                 _cleanup_strv_free_ char **files = NULL;
 
@@ -250,11 +246,8 @@ static int run(int argc, char *argv[]) {
                 else
                         log_debug("Flushed all binfmt_misc rules.");
 
-                STRV_FOREACH(f, files) {
-                        k = apply_file(*f, true);
-                        if (k < 0 && r >= 0)
-                                r = k;
-                }
+                STRV_FOREACH(f, files)
+                        RET_GATHER(r, apply_file(*f, true));
         }
 
         return r;
diff --git a/src/boot/bootctl-install.c b/src/boot/bootctl-install.c
index 397db7d3a2..7e85c2f08e 100644
--- a/src/boot/bootctl-install.c
+++ b/src/boot/bootctl-install.c
@@ -421,8 +421,7 @@ static int install_binaries(const char *esp_path, const char *arch, bool force)
                  * newer version, or other boot loader in place. */
                 if (arg_graceful && IN_SET(k, -ESTALE, -ESRCH))
                         continue;
-                if (k < 0 && r == 0)
-                        r = k;
+                RET_GATHER(r, k);
         }
 
         return r;
diff --git a/src/boot/bootctl-status.c b/src/boot/bootctl-status.c
index 0bfbf86e10..0f2e9204b7 100644
--- a/src/boot/bootctl-status.c
+++ b/src/boot/bootctl-status.c
@@ -483,17 +483,11 @@ int verb_status(int argc, char *argv[], void *userdata) {
                        "Not booted with EFI\n\n",
                        ansi_underline(), ansi_normal());
 
-        if (arg_esp_path) {
-                k = status_binaries(arg_esp_path, esp_uuid);
-                if (k < 0)
-                        r = k;
-        }
+        if (arg_esp_path)
+                RET_GATHER(r, status_binaries(arg_esp_path, esp_uuid));
 
-        if (!arg_root && is_efi_boot()) {
-                k = status_variables();
-                if (k < 0)
-                        r = k;
-        }
+        if (!arg_root && is_efi_boot())
+                RET_GATHER(r, status_variables());
 
         if (arg_esp_path || arg_xbootldr_path) {
                 _cleanup_(boot_config_free) BootConfig config = BOOT_CONFIG_NULL;
@@ -501,15 +495,13 @@ int verb_status(int argc, char *argv[], void *userdata) {
                 k = boot_config_load_and_select(&config,
                                                 arg_esp_path, esp_devid,
                                                 arg_xbootldr_path, xbootldr_devid);
-                if (k < 0)
-                        r = k;
-                else {
-                        k = status_entries(&config,
-                                           arg_esp_path, esp_uuid,
-                                           arg_xbootldr_path, xbootldr_uuid);
-                        if (k < 0)
-                                r = k;
-                }
+                RET_GATHER(r, k);
+
+                if (k >= 0)
+                        RET_GATHER(r,
+                                   status_entries(&config,
+                                                  arg_esp_path, esp_uuid,
+                                                  arg_xbootldr_path, xbootldr_uuid));
         }
 
         return r;
diff --git a/src/boot/bootctl-util.c b/src/boot/bootctl-util.c
index 6d886aba35..3cab875fa0 100644
--- a/src/boot/bootctl-util.c
+++ b/src/boot/bootctl-util.c
@@ -4,26 +4,27 @@
 
 #include "bootctl.h"
 #include "bootctl-util.h"
+#include "errno-util.h"
 #include "fileio.h"
 #include "stat-util.h"
 #include "sync-util.h"
 
 int sync_everything(void) {
-        int ret = 0, k;
+        int r = 0, k;
 
         if (arg_esp_path) {
                 k = syncfs_path(AT_FDCWD, arg_esp_path);
                 if (k < 0)
-                        ret = log_error_errno(k, "Failed to synchronize the ESP '%s': %m", arg_esp_path);
+                        RET_GATHER(r, log_error_errno(k, "Failed to synchronize the ESP '%s': %m", arg_esp_path));
         }
 
         if (arg_xbootldr_path) {
                 k = syncfs_path(AT_FDCWD, arg_xbootldr_path);
                 if (k < 0)
-                        ret = log_error_errno(k, "Failed to synchronize $BOOT '%s': %m", arg_xbootldr_path);
+                        RET_GATHER(r, log_error_errno(k, "Failed to synchronize $BOOT '%s': %m", arg_xbootldr_path));
         }
 
-        return ret;
+        return r;
 }
 
 const char *get_efi_arch(void) {
diff --git a/src/coredump/coredump.c b/src/coredump/coredump.c
index 24b019294b..8ae4a9f63f 100644
--- a/src/coredump/coredump.c
+++ b/src/coredump/coredump.c
@@ -245,8 +245,7 @@ static int fix_xattr(int fd, const Context *context) {
 
         assert(fd >= 0);
 
-        /* Attach some metadata to coredumps via extended
-         * attributes. Just because we can. */
+        /* Attach some metadata to coredumps via extended attributes. Just because we can. */
 
         for (unsigned i = 0; i < _META_MAX; i++) {
                 int k;
@@ -254,9 +253,8 @@ static int fix_xattr(int fd, const Context *context) {
                 if (isempty(context->meta[i]) || !xattrs[i])
                         continue;
 
-                k = fsetxattr(fd, xattrs[i], context->meta[i], strlen(context->meta[i]), XATTR_CREATE);
-                if (k < 0 && r == 0)
-                        r = -errno;
+                k = RET_NERRNO(fsetxattr(fd, xattrs[i], context->meta[i], strlen(context->meta[i]), XATTR_CREATE));
+                RET_GATHER(r, k);
         }
 
         return r;
diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index 7ff5db14d2..041789673f 100644
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -744,8 +744,7 @@ static int do_daemon_reload(void) {
                 k = bus_call_method(bus, bus_systemd_mgr, "StartUnit", &error, NULL, "ss", unit, "replace");
                 if (k < 0) {
                         log_error_errno(k, "Failed to (re)start %s: %s", unit, bus_error_message(&error, r));
-                        if (r == 0)
-                                r = k;
+                        RET_GATHER(r, k);
                 }
         }
 
diff --git a/src/gpt-auto-generator/gpt-auto-generator.c b/src/gpt-auto-generator/gpt-auto-generator.c
index 840d3b6ed1..4465038198 100644
--- a/src/gpt-auto-generator/gpt-auto-generator.c
+++ b/src/gpt-auto-generator/gpt-auto-generator.c
@@ -763,7 +763,7 @@ static int add_root_mount(void) {
 
 static int process_loader_partitions(DissectedPartition *esp, DissectedPartition *xbootldr) {
         sd_id128_t loader_uuid;
-        int r, ret = 0;
+        int r;
 
         assert(esp);
         assert(xbootldr);
@@ -797,26 +797,21 @@ static int process_loader_partitions(DissectedPartition *esp, DissectedPartition
         return 0;
 
 mount:
-        if (xbootldr->found) {
-                r = add_partition_xbootldr(xbootldr);
-                if (r < 0)
-                        ret = r;
-        }
+        r = 0;
 
-        if (esp->found) {
-                r = add_partition_esp(esp, xbootldr->found);
-                if (r < 0)
-                        ret = r;
-        }
+        if (xbootldr->found)
+                RET_GATHER(r, add_partition_xbootldr(xbootldr));
+        if (esp->found)
+                RET_GATHER(r, add_partition_esp(esp, xbootldr->found));
 
-        return ret;
+        return r;
 }
 
 static int enumerate_partitions(dev_t devnum) {
         _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL;
         _cleanup_(loop_device_unrefp) LoopDevice *loop = NULL;
         _cleanup_free_ char *devname = NULL;
-        int r, k;
+        int r;
 
         r = block_get_whole_disk(devnum, &devnum);
         if (r < 0)
@@ -856,45 +851,29 @@ static int enumerate_partitions(dev_t devnum) {
                 return ok ? 0 : r;
         }
 
-        if (m->partitions[PARTITION_SWAP].found) {
-                k = add_partition_swap(m->partitions + PARTITION_SWAP);
-                if (k < 0)
-                        r = k;
-        }
+        if (m->partitions[PARTITION_SWAP].found)
+                RET_GATHER(r, add_partition_swap(m->partitions + PARTITION_SWAP));
 
-        k = process_loader_partitions(m->partitions + PARTITION_ESP, m->partitions + PARTITION_XBOOTLDR);
-        if (k < 0)
-                r = k;
+        RET_GATHER(r, process_loader_partitions(m->partitions + PARTITION_ESP, m->partitions + PARTITION_XBOOTLDR));
 
-        if (m->partitions[PARTITION_HOME].found) {
-                k = add_partition_mount(PARTITION_HOME, m->partitions + PARTITION_HOME, "home", "/home", "Home Partition");
-                if (k < 0)
-                        r = k;
-        }
+        if (m->partitions[PARTITION_HOME].found)
+                RET_GATHER(r, add_partition_mount(PARTITION_HOME, m->partitions + PARTITION_HOME,
+                                                  "home", "/home", "Home Partition"));
 
-        if (m->partitions[PARTITION_SRV].found) {
-                k = add_partition_mount(PARTITION_SRV, m->partitions + PARTITION_SRV, "srv", "/srv", "Server Data Partition");
-                if (k < 0)
-                        r = k;
-        }
+        if (m->partitions[PARTITION_SRV].found)
+                RET_GATHER(r, add_partition_mount(PARTITION_SRV, m->partitions + PARTITION_SRV,
+                                                  "srv", "/srv", "Server Data Partition"));
 
-        if (m->partitions[PARTITION_VAR].found) {
-                k = add_partition_mount(PARTITION_VAR, m->partitions + PARTITION_VAR, "var", "/var", "Variable Data Partition");
-                if (k < 0)
-                        r = k;
-        }
+        if (m->partitions[PARTITION_VAR].found)
+                RET_GATHER(r, add_partition_mount(PARTITION_VAR, m->partitions + PARTITION_VAR,
+                                                  "var", "/var", "Variable Data Partition"));
 
-        if (m->partitions[PARTITION_TMP].found) {
-                k = add_partition_mount(PARTITION_TMP, m->partitions + PARTITION_TMP, "var-tmp", "/var/tmp", "Temporary Data Partition");
-                if (k < 0)
-                        r = k;
-        }
+        if (m->partitions[PARTITION_TMP].found)
+                RET_GATHER(r, add_partition_mount(PARTITION_TMP, m->partitions + PARTITION_TMP,
+                                                  "var-tmp", "/var/tmp", "Temporary Data Partition"));
 
-        if (m->partitions[PARTITION_ROOT].found) {
-                k = add_partition_root_rw(m->partitions + PARTITION_ROOT);
-                if (k < 0)
-                        r = k;
-        }
+        if (m->partitions[PARTITION_ROOT].found)
+                RET_GATHER(r, add_partition_root_rw(m->partitions + PARTITION_ROOT));
 
         return r;
 }
diff --git a/src/libsystemd-network/sd-dhcp-server.c b/src/libsystemd-network/sd-dhcp-server.c
index df6812bb8a..717dc195c5 100644
--- a/src/libsystemd-network/sd-dhcp-server.c
+++ b/src/libsystemd-network/sd-dhcp-server.c
@@ -1448,19 +1448,16 @@ on_error:
 
 int sd_dhcp_server_forcerenew(sd_dhcp_server *server) {
         DHCPLease *lease;
-        int k, r = 0;
+        int r = 0;
 
         assert_return(server, -EINVAL);
 
         log_dhcp_server(server, "FORCERENEW");
 
-        HASHMAP_FOREACH(lease, server->bound_leases_by_client_id) {
-                k = server_send_forcerenew(server, lease->address, lease->gateway,
-                                           lease->htype, lease->hlen, lease->chaddr);
-                if (k < 0)
-                        r = k;
-        }
-
+        HASHMAP_FOREACH(lease, server->bound_leases_by_client_id)
+                RET_GATHER(r,
+                           server_send_forcerenew(server, lease->address, lease->gateway,
+                                                  lease->htype, lease->hlen, lease->chaddr));
         return r;
 }
 
diff --git a/src/libsystemd/sd-device/device-enumerator.c b/src/libsystemd/sd-device/device-enumerator.c
index e072d976d3..766fadd22c 100644
--- a/src/libsystemd/sd-device/device-enumerator.c
+++ b/src/libsystemd/sd-device/device-enumerator.c
@@ -613,38 +613,30 @@ static int enumerator_add_parent_devices(
                 sd_device *device,
                 MatchFlag flags) {
 
-        int k, r = 0;
+        int r;
 
         assert(enumerator);
         assert(device);
 
         for (;;) {
-                k = sd_device_get_parent(device, &device);
-                if (k == -ENOENT) /* Reached the top? */
-                        break;
-                if (k < 0) {
-                        r = k;
-                        break;
-                }
+                r = sd_device_get_parent(device, &device);
+                if (r == -ENOENT) /* Reached the top? */
+                        return 0;
+                if (r < 0)
+                        return r;
 
-                k = test_matches(enumerator, device, flags);
-                if (k < 0) {
-                        r = k;
-                        break;
-                }
-                if (k == 0)
+                r = test_matches(enumerator, device, flags);
+                if (r < 0)
+                        return r;
+                if (r == 0)
                         continue;
 
-                k = device_enumerator_add_device(enumerator, device);
-                if (k < 0) {
-                        r = k;
-                        break;
-                }
-                if (k == 0) /* Exists already? Then no need to go further up. */
-                        break;
+                r = device_enumerator_add_device(enumerator, device);
+                if (r < 0)
+                        return r;
+                if (r == 0) /* Exists already? Then no need to go further up. */
+                        return 0;
         }
-
-        return r;
 }
 
 int device_enumerator_add_parent_devices(sd_device_enumerator *enumerator, sd_device *device) {
diff --git a/src/libsystemd/sd-netlink/netlink-message-nfnl.c b/src/libsystemd/sd-netlink/netlink-message-nfnl.c
index 582f623efe..a8cec2bd8b 100644
--- a/src/libsystemd/sd-netlink/netlink-message-nfnl.c
+++ b/src/libsystemd/sd-netlink/netlink-message-nfnl.c
@@ -184,7 +184,7 @@ int sd_nfnl_call_batch(
 
         _cleanup_free_ sd_netlink_message **replies = NULL;
         _cleanup_free_ uint32_t *serials = NULL;
-        int k, r;
+        int r;
 
         assert_return(nfnl, -EINVAL);
         assert_return(!netlink_pid_changed(nfnl), -ECHILD);
@@ -201,11 +201,9 @@ int sd_nfnl_call_batch(
         if (r < 0)
                 return r;
 
-        for (size_t i = 0; i < n_messages; i++) {
-                k = sd_netlink_read(nfnl, serials[i], usec, ret_messages ? replies + i : NULL);
-                if (k < 0 && r >= 0)
-                        r = k;
-        }
+        for (size_t i = 0; i < n_messages; i++)
+                RET_GATHER(r,
+                           sd_netlink_read(nfnl, serials[i], usec, ret_messages ? replies + i : NULL));
         if (r < 0)
                 return r;
 
diff --git a/src/modules-load/modules-load.c b/src/modules-load/modules-load.c
index 8e7f7a5eba..4adeef3afb 100644
--- a/src/modules-load/modules-load.c
+++ b/src/modules-load/modules-load.c
@@ -97,8 +97,7 @@ static int apply_file(struct kmod_ctx *ctx, const char *path, bool ignore_enoent
                 k = module_load_and_warn(ctx, l, true);
                 if (k == -ENOENT)
                         continue;
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, k);
         }
 
         return r;
@@ -186,11 +185,8 @@ static int run(int argc, char *argv[]) {
         r = 0;
 
         if (argc > optind) {
-                for (int i = optind; i < argc; i++) {
-                        k = apply_file(ctx, argv[i], false);
-                        if (k < 0 && r == 0)
-                                r = k;
-                }
+                for (int i = optind; i < argc; i++)
+                        RET_GATHER(r, apply_file(ctx, argv[i], false));
 
         } else {
                 _cleanup_strv_free_ char **files = NULL;
@@ -199,23 +195,15 @@ static int run(int argc, char *argv[]) {
                         k = module_load_and_warn(ctx, *i, true);
                         if (k == -ENOENT)
                                 continue;
-                        if (k < 0 && r == 0)
-                                r = k;
+                        RET_GATHER(r, k);
                 }
 
                 k = conf_files_list_nulstr(&files, ".conf", NULL, 0, conf_file_dirs);
-                if (k < 0) {
-                        log_error_errno(k, "Failed to enumerate modules-load.d files: %m");
-                        if (r == 0)
-                                r = k;
-                        return r;
-                }
+                if (k < 0)
+                        return log_error_errno(k, "Failed to enumerate modules-load.d files: %m");
 
-                STRV_FOREACH(fn, files) {
-                        k = apply_file(ctx, *fn, true);
-                        if (k < 0 && r == 0)
-                                r = k;
-                }
+                STRV_FOREACH(fn, files)
+                        RET_GATHER(r, apply_file(ctx, *fn, true));
         }
 
         return r;
diff --git a/src/network/generator/main.c b/src/network/generator/main.c
index 839ca80bec..3456fc4cf8 100644
--- a/src/network/generator/main.c
+++ b/src/network/generator/main.c
@@ -102,32 +102,22 @@ static int context_save(Context *context) {
         Network *network;
         NetDev *netdev;
         Link *link;
-        int k, r;
-        const char *p;
+        int r;
 
-        p = prefix_roota(arg_root, NETWORKD_UNIT_DIRECTORY);
+        const char *p = prefix_roota(arg_root, NETWORKD_UNIT_DIRECTORY);
 
         r = mkdir_p(p, 0755);
         if (r < 0)
                 return log_error_errno(r, "Failed to create directory " NETWORKD_UNIT_DIRECTORY ": %m");
 
-        HASHMAP_FOREACH(network, context->networks_by_name) {
-                k = network_save(network, p);
-                if (k < 0 && r >= 0)
-                        r = k;
-        }
+        HASHMAP_FOREACH(network, context->networks_by_name)
+                RET_GATHER(r, network_save(network, p));
 
-        HASHMAP_FOREACH(netdev, context->netdevs_by_name) {
-                k = netdev_save(netdev, p);
-                if (k < 0 && r >= 0)
-                        r = k;
-        }
+        HASHMAP_FOREACH(netdev, context->netdevs_by_name)
+                RET_GATHER(r, netdev_save(netdev, p));
 
-        HASHMAP_FOREACH(link, context->links_by_filename) {
-                k = link_save(link, p);
-                if (k < 0 && r >= 0)
-                        r = k;
-        }
+        HASHMAP_FOREACH(link, context->links_by_filename)
+                RET_GATHER(r, link_save(link, p));
 
         return r;
 }
diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c
index 2f77db95ab..c33ffa9576 100644
--- a/src/network/networkd-address.c
+++ b/src/network/networkd-address.c
@@ -994,7 +994,7 @@ int link_drop_ipv6ll_addresses(Link *link) {
 
 int link_drop_foreign_addresses(Link *link) {
         Address *address;
-        int k, r = 0;
+        int r = 0;
 
         assert(link);
         assert(link->network);
@@ -1054,9 +1054,7 @@ int link_drop_foreign_addresses(Link *link) {
                 if (!address_is_marked(address))
                         continue;
 
-                k = address_remove(address);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, address_remove(address));
         }
 
         return r;
@@ -1064,7 +1062,7 @@ int link_drop_foreign_addresses(Link *link) {
 
 int link_drop_managed_addresses(Link *link) {
         Address *address;
-        int k, r = 0;
+        int r = 0;
 
         assert(link);
 
@@ -1077,11 +1075,7 @@ int link_drop_managed_addresses(Link *link) {
                 if (!address_exists(address))
                         continue;
 
-                k = address_remove(address);
-                if (k < 0 && r >= 0) {
-                        r = k;
-                        continue;
-                }
+                RET_GATHER(r, address_remove(address));
         }
 
         return r;
diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 62dd892afa..c237295606 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -950,7 +950,7 @@ static Link *link_drop(Link *link) {
 }
 
 static int link_drop_foreign_config(Link *link) {
-        int k, r;
+        int r;
 
         assert(link);
         assert(link->manager);
@@ -967,48 +967,26 @@ static int link_drop_foreign_config(Link *link) {
 
         r = link_drop_foreign_routes(link);
 
-        k = link_drop_foreign_nexthops(link);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        k = link_drop_foreign_addresses(link);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        k = link_drop_foreign_neighbors(link);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        k = manager_drop_foreign_routing_policy_rules(link->manager);
-        if (k < 0 && r >= 0)
-                r = k;
+        RET_GATHER(r, link_drop_foreign_nexthops(link));
+        RET_GATHER(r, link_drop_foreign_addresses(link));
+        RET_GATHER(r, link_drop_foreign_neighbors(link));
+        RET_GATHER(r, manager_drop_foreign_routing_policy_rules(link->manager));
 
         return r;
 }
 
 static int link_drop_managed_config(Link *link) {
-        int k, r;
+        int r;
 
         assert(link);
         assert(link->manager);
 
         r = link_drop_managed_routes(link);
 
-        k = link_drop_managed_nexthops(link);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        k = link_drop_managed_addresses(link);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        k = link_drop_managed_neighbors(link);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        k = link_drop_managed_routing_policy_rules(link);
-        if (k < 0 && r >= 0)
-                r = k;
+        RET_GATHER(r, link_drop_managed_nexthops(link));
+        RET_GATHER(r, link_drop_managed_addresses(link));
+        RET_GATHER(r, link_drop_managed_neighbors(link));
+        RET_GATHER(r, link_drop_managed_routing_policy_rules(link));
 
         return r;
 }
diff --git a/src/network/networkd-manager.c b/src/network/networkd-manager.c
index b6ba216eee..ab5460db27 100644
--- a/src/network/networkd-manager.c
+++ b/src/network/networkd-manager.c
@@ -723,7 +723,7 @@ static int manager_enumerate_internal(
                 int (*process)(sd_netlink *, sd_netlink_message *, Manager *)) {
 
         _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *reply = NULL;
-        int k, r;
+        int r;
 
         assert(m);
         assert(nl);
@@ -739,11 +739,8 @@ static int manager_enumerate_internal(
                 return r;
 
         m->enumerating = true;
-        for (sd_netlink_message *reply_one = reply; reply_one; reply_one = sd_netlink_message_next(reply_one)) {
-                k = process(nl, reply_one, m);
-                if (k < 0 && r >= 0)
-                        r = k;
-        }
+        for (sd_netlink_message *reply_one = reply; reply_one; reply_one = sd_netlink_message_next(reply_one))
+                RET_GATHER(r, process(nl, reply_one, m));
         m->enumerating = false;
 
         return r;
diff --git a/src/network/networkd-neighbor.c b/src/network/networkd-neighbor.c
index f0f78b9c4a..e3c332eadb 100644
--- a/src/network/networkd-neighbor.c
+++ b/src/network/networkd-neighbor.c
@@ -377,7 +377,7 @@ static int neighbor_remove(Neighbor *neighbor) {
 
 int link_drop_foreign_neighbors(Link *link) {
         Neighbor *neighbor;
-        int k, r = 0;
+        int r = 0;
 
         assert(link);
         assert(link->network);
@@ -407,9 +407,7 @@ int link_drop_foreign_neighbors(Link *link) {
                 if (!neighbor_is_marked(neighbor))
                         continue;
 
-                k = neighbor_remove(neighbor);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, neighbor_remove(neighbor));
         }
 
         return r;
@@ -417,7 +415,7 @@ int link_drop_foreign_neighbors(Link *link) {
 
 int link_drop_managed_neighbors(Link *link) {
         Neighbor *neighbor;
-        int k, r = 0;
+        int r = 0;
 
         assert(link);
 
@@ -430,9 +428,7 @@ int link_drop_managed_neighbors(Link *link) {
                 if (!neighbor_exists(neighbor))
                         continue;
 
-                k = neighbor_remove(neighbor);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, neighbor_remove(neighbor));
         }
 
         return r;
diff --git a/src/network/networkd-nexthop.c b/src/network/networkd-nexthop.c
index 0820e0db2d..eed28440c2 100644
--- a/src/network/networkd-nexthop.c
+++ b/src/network/networkd-nexthop.c
@@ -687,7 +687,7 @@ static void manager_mark_nexthops(Manager *manager, bool foreign, const Link *ex
 
 static int manager_drop_marked_nexthops(Manager *manager) {
         NextHop *nexthop;
-        int k, r = 0;
+        int r = 0;
 
         assert(manager);
 
@@ -695,9 +695,7 @@ static int manager_drop_marked_nexthops(Manager *manager) {
                 if (!nexthop_is_marked(nexthop))
                         continue;
 
-                k = nexthop_remove(nexthop);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, nexthop_remove(nexthop));
         }
 
         return r;
@@ -705,7 +703,7 @@ static int manager_drop_marked_nexthops(Manager *manager) {
 
 int link_drop_foreign_nexthops(Link *link) {
         NextHop *nexthop;
-        int k, r = 0;
+        int r = 0;
 
         assert(link);
         assert(link->manager);
@@ -741,23 +739,17 @@ int link_drop_foreign_nexthops(Link *link) {
                 if (!nexthop_is_marked(nexthop))
                         continue;
 
-                k = nexthop_remove(nexthop);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, nexthop_remove(nexthop));
         }
 
         manager_mark_nexthops(link->manager, /* foreign = */ true, NULL);
 
-        k = manager_drop_marked_nexthops(link->manager);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        return r;
+        return RET_GATHER(r, manager_drop_marked_nexthops(link->manager));
 }
 
 int link_drop_managed_nexthops(Link *link) {
         NextHop *nexthop;
-        int k, r = 0;
+        int r = 0;
 
         assert(link);
         assert(link->manager);
@@ -775,18 +767,12 @@ int link_drop_managed_nexthops(Link *link) {
                 if (!nexthop_exists(nexthop))
                         continue;
 
-                k = nexthop_remove(nexthop);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, nexthop_remove(nexthop));
         }
 
         manager_mark_nexthops(link->manager, /* foreign = */ false, link);
 
-        k = manager_drop_marked_nexthops(link->manager);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        return r;
+        return RET_GATHER(r, manager_drop_marked_nexthops(link->manager));
 }
 
 void link_foreignize_nexthops(Link *link) {
diff --git a/src/network/networkd-route.c b/src/network/networkd-route.c
index f1f4447ec7..44dc63b642 100644
--- a/src/network/networkd-route.c
+++ b/src/network/networkd-route.c
@@ -857,7 +857,7 @@ static void manager_mark_routes(Manager *manager, bool foreign, const Link *exce
 
 static int manager_drop_marked_routes(Manager *manager) {
         Route *route;
-        int k, r = 0;
+        int r = 0;
 
         assert(manager);
 
@@ -865,9 +865,7 @@ static int manager_drop_marked_routes(Manager *manager) {
                 if (!route_is_marked(route))
                         continue;
 
-                k = route_remove(route);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, route_remove(route));
         }
 
         return r;
@@ -907,7 +905,7 @@ static void link_unmark_wireguard_routes(Link *link) {
 
 int link_drop_foreign_routes(Link *link) {
         Route *route;
-        int k, r;
+        int r;
 
         assert(link);
         assert(link->manager);
@@ -962,23 +960,17 @@ int link_drop_foreign_routes(Link *link) {
                 if (!route_is_marked(route))
                         continue;
 
-                k = route_remove(route);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, route_remove(route));
         }
 
         manager_mark_routes(link->manager, /* foreign = */ true, NULL);
 
-        k = manager_drop_marked_routes(link->manager);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        return r;
+        return RET_GATHER(r, manager_drop_marked_routes(link->manager));
 }
 
 int link_drop_managed_routes(Link *link) {
         Route *route;
-        int k, r = 0;
+        int r = 0;
 
         assert(link);
 
@@ -994,18 +986,12 @@ int link_drop_managed_routes(Link *link) {
                 if (!route_exists(route))
                         continue;
 
-                k = route_remove(route);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, route_remove(route));
         }
 
         manager_mark_routes(link->manager, /* foreign = */ false, link);
 
-        k = manager_drop_marked_routes(link->manager);
-        if (k < 0 && r >= 0)
-                r = k;
-
-        return r;
+        return RET_GATHER(r, manager_drop_marked_routes(link->manager));
 }
 
 void link_foreignize_routes(Link *link) {
diff --git a/src/network/networkd-routing-policy-rule.c b/src/network/networkd-routing-policy-rule.c
index ee3b1b275e..0cb5831ea3 100644
--- a/src/network/networkd-routing-policy-rule.c
+++ b/src/network/networkd-routing-policy-rule.c
@@ -684,7 +684,7 @@ static void manager_mark_routing_policy_rules(Manager *m, bool foreign, const Li
 
 int manager_drop_routing_policy_rules_internal(Manager *m, bool foreign, const Link *except) {
         RoutingPolicyRule *rule;
-        int k, r = 0;
+        int r = 0;
 
         assert(m);
 
@@ -694,9 +694,7 @@ int manager_drop_routing_policy_rules_internal(Manager *m, bool foreign, const L
                 if (!routing_policy_rule_is_marked(rule))
                         continue;
 
-                k = routing_policy_rule_remove(rule);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, routing_policy_rule_remove(rule));
         }
 
         return r;
diff --git a/src/shared/bus-util.c b/src/shared/bus-util.c
index d4c91fa3aa..4123152d93 100644
--- a/src/shared/bus-util.c
+++ b/src/shared/bus-util.c
@@ -516,14 +516,8 @@ int bus_track_add_name_many(sd_bus_track *t, char **l) {
 
         /* Continues adding after failure, and returns the first failure. */
 
-        STRV_FOREACH(i, l) {
-                int k;
-
-                k = sd_bus_track_add_name(t, *i);
-                if (k < 0 && r >= 0)
-                        r = k;
-        }
-
+        STRV_FOREACH(i, l)
+                RET_GATHER(r, sd_bus_track_add_name(t, *i));
         return r;
 }
 
diff --git a/src/shared/devnode-acl.c b/src/shared/devnode-acl.c
index 92a2aff3dc..b239699e8a 100644
--- a/src/shared/devnode-acl.c
+++ b/src/shared/devnode-acl.c
@@ -218,8 +218,8 @@ int devnode_acl_all(const char *seat,
                 k = devnode_acl(n, flush, del, old_uid, add, new_uid);
                 if (k == -ENOENT)
                         log_debug("Device %s disappeared while setting ACLs", n);
-                else if (k < 0 && r == 0)
-                        r = k;
+                else
+                        RET_GATHER(r, k);
         }
 
         return r;
diff --git a/src/shared/nscd-flush.c b/src/shared/nscd-flush.c
index dfc7db6964..6df18d7aac 100644
--- a/src/shared/nscd-flush.c
+++ b/src/shared/nscd-flush.c
@@ -128,21 +128,15 @@ static int nscd_flush_cache_one(const char *database, usec_t end) {
 }
 
 int nscd_flush_cache(char **databases) {
-        usec_t end;
         int r = 0;
 
-        /* Tries to invalidate the specified database in nscd. We do this carefully, with a 5s timeout, so that we
-         * don't block indefinitely on another service. */
+        /* Tries to invalidate the specified database in nscd. We do this carefully, with a 5s timeout,
+         * so that we don't block indefinitely on another service. */
 
-        end = usec_add(now(CLOCK_MONOTONIC), NSCD_FLUSH_CACHE_TIMEOUT_USEC);
+        usec_t end = usec_add(now(CLOCK_MONOTONIC), NSCD_FLUSH_CACHE_TIMEOUT_USEC);
 
-        STRV_FOREACH(i, databases) {
-                int k;
-
-                k = nscd_flush_cache_one(*i, end);
-                if (k < 0 && r >= 0)
-                        r = k;
-        }
+        STRV_FOREACH(i, databases)
+                RET_GATHER(r, nscd_flush_cache_one(*i, end));
 
         return r;
 }
diff --git a/src/sysctl/sysctl.c b/src/sysctl/sysctl.c
index c9b277b124..ca41f02fdd 100644
--- a/src/sysctl/sysctl.c
+++ b/src/sysctl/sysctl.c
@@ -113,7 +113,7 @@ static int sysctl_write_or_warn(const char *key, const char *value, bool ignore_
 static int apply_glob_option_with_prefix(OrderedHashmap *sysctl_options, Option *option, const char *prefix) {
         _cleanup_strv_free_ char **paths = NULL;
         _cleanup_free_ char *pattern = NULL;
-        int r, k;
+        int r;
 
         assert(sysctl_options);
         assert(option);
@@ -173,28 +173,23 @@ static int apply_glob_option_with_prefix(OrderedHashmap *sysctl_options, Option
                         continue;
                 }
 
-                k = sysctl_write_or_warn(key, option->value,
-                                         /* ignore_failure = */ option->ignore_failure,
-                                         /* ignore_enoent = */ !arg_strict);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r,
+                           sysctl_write_or_warn(key, option->value,
+                                                /* ignore_failure = */ option->ignore_failure,
+                                                /* ignore_enoent = */ !arg_strict));
         }
 
         return r;
 }
 
 static int apply_glob_option(OrderedHashmap *sysctl_options, Option *option) {
-        int r = 0, k;
+        int r = 0;
 
         if (strv_isempty(arg_prefixes))
                 return apply_glob_option_with_prefix(sysctl_options, option, NULL);
 
-        STRV_FOREACH(i, arg_prefixes) {
-                k = apply_glob_option_with_prefix(sysctl_options, option, *i);
-                if (k < 0 && r >= 0)
-                        r = k;
-        }
-
+        STRV_FOREACH(i, arg_prefixes)
+                RET_GATHER(r, apply_glob_option_with_prefix(sysctl_options, option, *i));
         return r;
 }
 
@@ -215,8 +210,7 @@ static int apply_all(OrderedHashmap *sysctl_options) {
                         k = sysctl_write_or_warn(option->key, option->value,
                                                  /* ignore_failure = */ option->ignore_failure,
                                                  /* ignore_enoent = */ !arg_strict);
-                if (k < 0 && r >= 0)
-                        r = k;
+                RET_GATHER(r, k);
         }
 
         return r;
@@ -444,7 +438,7 @@ static int parse_argv(int argc, char *argv[]) {
 
 static int run(int argc, char *argv[]) {
         _cleanup_ordered_hashmap_free_ OrderedHashmap *sysctl_options = NULL;
-        int r, k;
+        int r;
 
         r = parse_argv(argc, argv);
         if (r <= 0)
@@ -455,15 +449,11 @@ static int run(int argc, char *argv[]) {
         umask(0022);
 
         if (argc > optind) {
-                int i;
-
                 r = 0;
 
-                for (i = optind; i < argc; i++) {
-                        k = parse_file(&sysctl_options, argv[i], false);
-                        if (k < 0 && r == 0)
-                                r = k;
-                }
+                for (int i = optind; i < argc; i++)
+                        RET_GATHER(r, parse_file(&sysctl_options, argv[i], false));
+
         } else {
                 _cleanup_strv_free_ char **files = NULL;
 
@@ -477,20 +467,13 @@ static int run(int argc, char *argv[]) {
                         return cat_files(NULL, files, 0);
                 }
 
-                STRV_FOREACH(f, files) {
-                        k = parse_file(&sysctl_options, *f, true);
-                        if (k < 0 && r == 0)
-                                r = k;
-                }
+                STRV_FOREACH(f, files)
+                        RET_GATHER(r, parse_file(&sysctl_options, *f, true));
 
-                k = read_credential_lines(&sysctl_options);
-                if (k < 0 && r == 0)
-                        r = k;
+                RET_GATHER(r, read_credential_lines(&sysctl_options));
         }
 
-        k = apply_all(sysctl_options);
-        if (k < 0 && r == 0)
-                r = k;
+        RET_GATHER(r, apply_all(sysctl_options));
 
         return r;
 }
diff --git a/src/systemctl/systemctl-set-property.c b/src/systemctl/systemctl-set-property.c
index b8d702ac0e..5f4b810525 100644
--- a/src/systemctl/systemctl-set-property.c
+++ b/src/systemctl/systemctl-set-property.c
@@ -46,7 +46,7 @@ static int set_property_one(sd_bus *bus, const char *name, char **properties) {
 int verb_set_property(int argc, char *argv[], void *userdata) {
         sd_bus *bus;
         _cleanup_strv_free_ char **names = NULL;
-        int r, k;
+        int r;
 
         r = acquire_bus(BUS_MANAGER, &bus);
         if (r < 0)
@@ -59,10 +59,7 @@ int verb_set_property(int argc, char *argv[], void *userdata) {
                 return log_error_errno(r, "Failed to expand '%s' into names: %m", argv[1]);
 
         r = 0;
-        STRV_FOREACH(name, names) {
-                k = set_property_one(bus, *name, strv_skip(argv, 2));
-                if (k < 0 && r >= 0)
-                        r = k;
-        }
+        STRV_FOREACH(name, names)
+                RET_GATHER(r, set_property_one(bus, *name, strv_skip(argv, 2)));
         return r;
 }
diff --git a/src/sysusers/sysusers.c b/src/sysusers/sysusers.c
index 8acda4ef25..09af6dcd93 100644
--- a/src/sysusers/sysusers.c
+++ b/src/sysusers/sysusers.c
@@ -107,7 +107,9 @@ static OrderedHashmap *members = NULL;
 
 static Hashmap *database_by_uid = NULL, *database_by_username = NULL;
 static Hashmap *database_by_gid = NULL, *database_by_groupname = NULL;
-static Set *database_users = NULL, *database_groups = NULL;
+
+/* A helper set to hold names that are used by database_by_{uid,gid,username,groupname} above. */
+static Set *names = NULL;
 
 static uid_t search_uid = UID_INVALID;
 static UidRange *uid_range = NULL;
@@ -122,10 +124,9 @@ STATIC_DESTRUCTOR_REGISTER(todo_uids, ordered_hashmap_freep);
 STATIC_DESTRUCTOR_REGISTER(todo_gids, ordered_hashmap_freep);
 STATIC_DESTRUCTOR_REGISTER(database_by_uid, hashmap_freep);
 STATIC_DESTRUCTOR_REGISTER(database_by_username, hashmap_freep);
-STATIC_DESTRUCTOR_REGISTER(database_users, set_free_freep);
 STATIC_DESTRUCTOR_REGISTER(database_by_gid, hashmap_freep);
 STATIC_DESTRUCTOR_REGISTER(database_by_groupname, hashmap_freep);
-STATIC_DESTRUCTOR_REGISTER(database_groups, set_free_freep);
+STATIC_DESTRUCTOR_REGISTER(names, set_free_freep);
 STATIC_DESTRUCTOR_REGISTER(uid_range, uid_range_freep);
 STATIC_DESTRUCTOR_REGISTER(arg_root, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_image, freep);
@@ -184,31 +185,35 @@ static int load_user_database(void) {
         if (r < 0)
                 return r;
 
-        r = set_ensure_allocated(&database_users, NULL);
+        /* Note that we use NULL, i.e. trivial_hash_ops here, so identical strings can exist in the set. */
+        r = set_ensure_allocated(&names, NULL);
         if (r < 0)
                 return r;
 
         while ((r = fgetpwent_sane(f, &pw)) > 0) {
-                char *n;
-                int k, q;
 
-                n = strdup(pw->pw_name);
+                char *n = strdup(pw->pw_name);
                 if (!n)
                         return -ENOMEM;
 
-                k = set_put(database_users, n);
-                if (k < 0) {
-                        free(n);
-                        return k;
-                }
+                r = set_consume(names, n);
+                if (r < 0)
+                        return r;
+                assert(r > 0);  /* The set uses pointer comparisons, so n must not be in the set. */
 
-                k = hashmap_put(database_by_username, n, UID_TO_PTR(pw->pw_uid));
-                if (k < 0 && k != -EEXIST)
-                        return k;
+                r = hashmap_put(database_by_username, n, UID_TO_PTR(pw->pw_uid));
+                if (r == -EEXIST)
+                        log_debug_errno(r, "%s: user '%s' is listed twice, ignoring duplicate uid.",
+                                        passwd_path, n);
+                else if (r < 0)
+                        return r;
 
-                q = hashmap_put(database_by_uid, UID_TO_PTR(pw->pw_uid), n);
-                if (q < 0 && q != -EEXIST)
-                        return q;
+                r = hashmap_put(database_by_uid, UID_TO_PTR(pw->pw_uid), n);
+                if (r == -EEXIST)
+                        log_debug_errno(r, "%s: uid "UID_FMT" is listed twice, ignoring duplicate name.",
+                                        passwd_path, pw->pw_uid);
+                else if (r < 0)
+                        return r;
         }
         return r;
 }
@@ -232,31 +237,35 @@ static int load_group_database(void) {
         if (r < 0)
                 return r;
 
-        r = set_ensure_allocated(&database_groups, NULL);
+        /* Note that we use NULL, i.e. trivial_hash_ops here, so identical strings can exist in the set. */
+        r = set_ensure_allocated(&names, NULL);
         if (r < 0)
                 return r;
 
         while ((r = fgetgrent_sane(f, &gr)) > 0) {
-                char *n;
-                int k, q;
 
-                n = strdup(gr->gr_name);
+                char *n = strdup(gr->gr_name);
                 if (!n)
                         return -ENOMEM;
 
-                k = set_put(database_groups, n);
-                if (k < 0) {
-                        free(n);
-                        return k;
-                }
+                r = set_consume(names, n);
+                if (r < 0)
+                        return r;
+                assert(r > 0);  /* The set uses pointer comparisons, so n must not be in the set. */
 
-                k = hashmap_put(database_by_groupname, n, GID_TO_PTR(gr->gr_gid));
-                if (k < 0 && k != -EEXIST)
-                        return k;
+                r = hashmap_put(database_by_groupname, n, GID_TO_PTR(gr->gr_gid));
+                if (r == -EEXIST)
+                        log_debug_errno(r, "%s: group '%s' is listed twice, ignoring duplicate gid.",
+                                        group_path, n);
+                else if (r < 0)
+                        return r;
 
-                q = hashmap_put(database_by_gid, GID_TO_PTR(gr->gr_gid), n);
-                if (q < 0 && q != -EEXIST)
-                        return q;
+                r = hashmap_put(database_by_gid, GID_TO_PTR(gr->gr_gid), n);
+                if (r == -EEXIST)
+                        log_debug_errno(r, "%s: gid "GID_FMT" is listed twice, ignoring duplicate name.",
+                                        group_path, gr->gr_gid);
+                else if (r < 0)
+                        return r;
         }
         return r;
 }
diff --git a/src/test/test-errno-util.c b/src/test/test-errno-util.c
index d3d022c33f..62a508c4c9 100644
--- a/src/test/test-errno-util.c
+++ b/src/test/test-errno-util.c
@@ -78,4 +78,15 @@ TEST(UNPROTECT_ERRNO) {
         assert_se(errno == 4711);
 }
 
+TEST(RET_GATHER) {
+        int x = 0, y = 2;
+
+        assert_se(RET_GATHER(x, 5) == 0);
+        assert_se(RET_GATHER(x, -5) == -5);
+        assert_se(RET_GATHER(x, -1) == -5);
+
+        assert_se(RET_GATHER(x, y++) == -5);
+        assert_se(y == 3);
+}
+
 DEFINE_TEST_MAIN(LOG_INFO);
diff --git a/src/udev/udev-builtin-uaccess.c b/src/udev/udev-builtin-uaccess.c
index 36c993cbb0..da42ef59b0 100644
--- a/src/udev/udev-builtin-uaccess.c
+++ b/src/udev/udev-builtin-uaccess.c
@@ -12,6 +12,7 @@
 
 #include "device-util.h"
 #include "devnode-acl.h"
+#include "errno-util.h"
 #include "login-util.h"
 #include "log.h"
 #include "udev-builtin.h"
@@ -66,8 +67,7 @@ finish:
                 k = devnode_acl(path, true, false, 0, false, 0);
                 if (k < 0) {
                         log_device_full_errno(dev, k == -ENOENT ? LOG_DEBUG : LOG_ERR, k, "Failed to apply ACL: %m");
-                        if (r >= 0)
-                                r = k;
+                        RET_GATHER(r, k);
                 }
         }