Run our #else/#endif annotator on our source code.

129 files changed, 336 insertions, 336 deletions

diff --git a/src/or/addressmap.c b/src/or/addressmap.c
index f278564e80..ebafc1cc00 100644
--- a/src/or/addressmap.c
+++ b/src/or/addressmap.c
@@ -814,7 +814,7 @@ parse_virtual_addr_network(const char *val, sa_family_t family,
                    ipv6?"IPv6":"");
     return -1;
   }
-#endif
+#endif /* 0 */
 
   if (bits > max_prefix_bits) {
     if (msg)
@@ -1044,7 +1044,7 @@ addressmap_register_virtual_address(int type, char *new_address)
              safe_str_client(*addrp),
              safe_str_client(new_address));
   }
-#endif
+#endif /* 0 */
 
   return *addrp;
 }
diff --git a/src/or/addressmap.h b/src/or/addressmap.h
index 80f453b4c1..1544b76e10 100644
--- a/src/or/addressmap.h
+++ b/src/or/addressmap.h
@@ -59,7 +59,7 @@ typedef struct virtual_addr_conf_t {
 
 STATIC void get_random_virtual_addr(const virtual_addr_conf_t *conf,
                                     tor_addr_t *addr_out);
-#endif
+#endif /* defined(ADDRESSMAP_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_ADDRESSMAP_H) */
 
diff --git a/src/or/bridges.c b/src/or/bridges.c
index 1eec4e39ec..1c748b4156 100644
--- a/src/or/bridges.c
+++ b/src/or/bridges.c
@@ -310,7 +310,7 @@ learned_router_identity(const tor_addr_t *addr, uint16_t port,
     memcpy(&bridge->ed25519_identity, ed_id, sizeof(*ed_id));
     learned = 1;
   }
-#endif
+#endif /* 0 */
   if (learned) {
     char *transport_info = NULL;
     const char *transport_name =
diff --git a/src/or/bridges.h b/src/or/bridges.h
index 19341818f4..263c7d51b2 100644
--- a/src/or/bridges.h
+++ b/src/or/bridges.h
@@ -66,5 +66,5 @@ MOCK_DECL(download_status_t *, get_bridge_dl_status_by_id,
 
 void bridges_free_all(void);
 
-#endif
+#endif /* !defined(TOR_BRIDGES_H) */
 
diff --git a/src/or/channel.c b/src/or/channel.c
index 9e482a2b37..faece55981 100644
--- a/src/or/channel.c
+++ b/src/or/channel.c
@@ -701,7 +701,7 @@ channel_remove_from_digest_map(channel_t *chan)
 
     return;
   }
-#endif
+#endif /* 0 */
 
   /* Pull it out of its list, wherever that list is */
   TOR_LIST_REMOVE(chan, next_with_same_id);
@@ -1832,7 +1832,7 @@ cell_queue_entry_is_padding(cell_queue_entry_t *q)
 
   return 0;
 }
-#endif
+#endif /* 0 */
 
 /**
  * Allocate a new cell queue entry for a fixed-size cell
diff --git a/src/or/channel.h b/src/or/channel.h
index 8c776c53f2..204b244293 100644
--- a/src/or/channel.h
+++ b/src/or/channel.h
@@ -487,7 +487,7 @@ STATIC void cell_queue_entry_free(cell_queue_entry_t *q, int handed_off);
 
 void channel_write_cell_generic_(channel_t *chan, const char *cell_type,
                                  void *cell, cell_queue_entry_t *q);
-#endif
+#endif /* defined(CHANNEL_PRIVATE_) */
 
 /* Channel operations for subclasses and internal use only */
 
@@ -580,7 +580,7 @@ void channel_do_open_actions(channel_t *chan);
 extern uint64_t estimated_total_queue_size;
 #endif
 
-#endif
+#endif /* defined(TOR_CHANNEL_INTERNAL_) */
 
 /* Helper functions to perform operations on channels */
 
@@ -719,5 +719,5 @@ int packed_cell_is_destroy(channel_t *chan,
 /* Declare the handle helpers */
 HANDLE_DECL(channel, channel_s,)
 
-#endif
+#endif /* !defined(TOR_CHANNEL_H) */
 
diff --git a/src/or/channelpadding.h b/src/or/channelpadding.h
index a227e27d5b..58bf741d5c 100644
--- a/src/or/channelpadding.h
+++ b/src/or/channelpadding.h
@@ -41,5 +41,5 @@ int channelpadding_get_circuits_available_timeout(void);
 unsigned int channelpadding_get_channel_idle_timeout(const channel_t *, int);
 void channelpadding_new_consensus_params(networkstatus_t *ns);
 
-#endif
+#endif /* !defined(TOR_CHANNELPADDING_H) */
 
diff --git a/src/or/channeltls.c b/src/or/channeltls.c
index a08e7cdfdb..7f68824482 100644
--- a/src/or/channeltls.c
+++ b/src/or/channeltls.c
@@ -1044,7 +1044,7 @@ channel_tls_time_process_cell(cell_t *cell, channel_tls_t *chan, int *time,
 
   *time += time_passed;
 }
-#endif
+#endif /* defined(KEEP_TIMING_STATS) */
 
 /**
  * Handle an incoming cell on a channel_tls_t
@@ -1072,9 +1072,9 @@ channel_tls_handle_cell(cell_t *cell, or_connection_t *conn)
     channel_tls_time_process_cell(cl, cn, & tp ## time ,            \
                              channel_tls_process_ ## tp ## _cell);  \
     } STMT_END
-#else
+#else /* !(defined(KEEP_TIMING_STATS)) */
 #define PROCESS_CELL(tp, cl, cn) channel_tls_process_ ## tp ## _cell(cl, cn)
-#endif
+#endif /* defined(KEEP_TIMING_STATS) */
 
   tor_assert(cell);
   tor_assert(conn);
@@ -1204,7 +1204,7 @@ channel_tls_handle_var_cell(var_cell_t *var_cell, or_connection_t *conn)
     /* remember which second it is, for next time */
     current_second = now;
   }
-#endif
+#endif /* defined(KEEP_TIMING_STATS) */
 
   tor_assert(var_cell);
   tor_assert(conn);
@@ -1579,7 +1579,7 @@ channel_tls_process_versions_cell(var_cell_t *cell, channel_tls_t *chan)
       connection_or_close_normally(chan->conn, 1);
       return;
     }
-#endif
+#endif /* defined(DISABLE_V3_LINKPROTO_SERVERSIDE) */
 
     if (send_versions) {
       if (connection_or_send_versions(chan->conn, 1) < 0) {
diff --git a/src/or/channeltls.h b/src/or/channeltls.h
index 1f9a39d8a4..d9c4239c3a 100644
--- a/src/or/channeltls.h
+++ b/src/or/channeltls.h
@@ -26,7 +26,7 @@ struct channel_tls_s {
   or_connection_t *conn;
 };
 
-#endif /* TOR_CHANNEL_INTERNAL_ */
+#endif /* defined(TOR_CHANNEL_INTERNAL_) */
 
 channel_t * channel_tls_connect(const tor_addr_t *addr, uint16_t port,
                                 const char *id_digest,
@@ -69,7 +69,7 @@ STATIC void channel_tls_process_auth_challenge_cell(var_cell_t *cell,
 STATIC void channel_tls_common_init(channel_tls_t *tlschan);
 STATIC void channel_tls_process_authenticate_cell(var_cell_t *cell,
                                                   channel_tls_t *tlschan);
-#endif
+#endif /* defined(CHANNELTLS_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CHANNELTLS_H) */
 
diff --git a/src/or/circpathbias.c b/src/or/circpathbias.c
index 4c0bd9e455..f4bd5ea2fa 100644
--- a/src/or/circpathbias.c
+++ b/src/or/circpathbias.c
@@ -292,7 +292,7 @@ pathbias_is_new_circ_attempt(origin_circuit_t *circ)
   return circ->cpath &&
          circ->cpath->next != circ->cpath &&
          circ->cpath->next->state == CPATH_STATE_AWAITING_KEYS;
-#else
+#else /* !(defined(N2N_TAGGING_IS_POSSIBLE)) */
   /* If tagging attacks are no longer possible, we probably want to
    * count bias from the first hop. However, one could argue that
    * timing-based tagging is still more useful than per-hop failure.
@@ -300,7 +300,7 @@ pathbias_is_new_circ_attempt(origin_circuit_t *circ)
    */
   return circ->cpath &&
          circ->cpath->state == CPATH_STATE_AWAITING_KEYS;
-#endif
+#endif /* defined(N2N_TAGGING_IS_POSSIBLE) */
 }
 
 /**
diff --git a/src/or/circpathbias.h b/src/or/circpathbias.h
index 2a4c316807..c9e572d2ae 100644
--- a/src/or/circpathbias.h
+++ b/src/or/circpathbias.h
@@ -25,5 +25,5 @@ void pathbias_mark_use_success(origin_circuit_t *circ);
 void pathbias_mark_use_rollback(origin_circuit_t *circ);
 const char *pathbias_state_to_string(path_state_t state);
 
-#endif
+#endif /* !defined(TOR_CIRCPATHBIAS_H) */
 
diff --git a/src/or/circuitbuild.c b/src/or/circuitbuild.c
index 279308afcb..dea87e5915 100644
--- a/src/or/circuitbuild.c
+++ b/src/or/circuitbuild.c
@@ -1566,7 +1566,7 @@ circuit_truncated(origin_circuit_t *circ, crypt_path_t *layer, int reason)
 
   log_info(LD_CIRC, "finished");
   return 0;
-#endif
+#endif /* 0 */
 }
 
 /** Given a response payload and keys, initialize, then send a created
@@ -2104,7 +2104,7 @@ pick_tor2web_rendezvous_node(router_crn_flags_t flags,
 
   return rp_node;
 }
-#endif
+#endif /* defined(ENABLE_TOR2WEB_MODE) || defined(TOR_UNIT_TESTS) */
 
 /* Pick a Rendezvous Point for our HS circuits according to <b>flags</b>. */
 static const node_t *
@@ -2140,7 +2140,7 @@ pick_rendezvous_node(router_crn_flags_t flags)
              "Unable to find a random rendezvous point that is reachable via "
              "a direct connection, falling back to a 3-hop path.");
   }
-#endif
+#endif /* defined(ENABLE_TOR2WEB_MODE) */
 
   return router_choose_random_node(NULL, options->ExcludeNodes, flags);
 }
@@ -2430,7 +2430,7 @@ cpath_get_n_hops(crypt_path_t **head_ptr)
   return n_hops;
 }
 
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /** A helper function used by onion_extend_cpath(). Use <b>purpose</b>
  * and <b>state</b> and the cpath <b>head</b> (currently populated only
diff --git a/src/or/circuitbuild.h b/src/or/circuitbuild.h
index 62a6367ed2..b8a651e055 100644
--- a/src/or/circuitbuild.h
+++ b/src/or/circuitbuild.h
@@ -86,9 +86,9 @@ STATIC const node_t *pick_tor2web_rendezvous_node(router_crn_flags_t flags,
                                                   const or_options_t *options);
 unsigned int cpath_get_n_hops(crypt_path_t **head_ptr);
 
-#endif
+#endif /* defined(ENABLE_TOR2WEB_MODE) || defined(TOR_UNIT_TESTS) */
 
-#endif
+#endif /* defined(CIRCUITBUILD_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CIRCUITBUILD_H) */
 
diff --git a/src/or/circuitlist.c b/src/or/circuitlist.c
index 5cc6252325..a0ff74190e 100644
--- a/src/or/circuitlist.c
+++ b/src/or/circuitlist.c
@@ -1434,7 +1434,7 @@ circuit_unlink_all_from_channel(channel_t *chan, int reason)
       smartlist_free(detached_2);
     }
   }
-#endif
+#endif /* defined(DEBUG_CIRCUIT_UNLINK_ALL) */
 
   SMARTLIST_FOREACH_BEGIN(detached, circuit_t *, circ) {
     int mark = 0;
diff --git a/src/or/circuitlist.h b/src/or/circuitlist.h
index b882b2c6a8..5d0da15ca8 100644
--- a/src/or/circuitlist.h
+++ b/src/or/circuitlist.h
@@ -86,7 +86,7 @@ STATIC size_t n_cells_in_circ_queues(const circuit_t *c);
 STATIC uint32_t circuit_max_queued_data_age(const circuit_t *c, uint32_t now);
 STATIC uint32_t circuit_max_queued_cell_age(const circuit_t *c, uint32_t now);
 STATIC uint32_t circuit_max_queued_item_age(const circuit_t *c, uint32_t now);
-#endif
+#endif /* defined(CIRCUITLIST_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CIRCUITLIST_H) */
 
diff --git a/src/or/circuitmux.c b/src/or/circuitmux.c
index ee0d5c718b..38ab56b6dc 100644
--- a/src/or/circuitmux.c
+++ b/src/or/circuitmux.c
@@ -185,7 +185,7 @@ struct chanid_circid_muxinfo_t {
   circuitmux_assert_okay(cmux)
 #else
 #define circuitmux_assert_okay_paranoid(cmux)
-#endif
+#endif /* defined(CMUX_PARANOIA) */
 
 /*
  * Static function declarations
diff --git a/src/or/circuitmux.h b/src/or/circuitmux.h
index 42a46aaa47..3e7496ea1c 100644
--- a/src/or/circuitmux.h
+++ b/src/or/circuitmux.h
@@ -156,5 +156,5 @@ void circuitmux_mark_destroyed_circids_usable(circuitmux_t *cmux,
 MOCK_DECL(int, circuitmux_compare_muxes,
           (circuitmux_t *cmux_1, circuitmux_t *cmux_2));
 
-#endif /* TOR_CIRCUITMUX_H */
+#endif /* !defined(TOR_CIRCUITMUX_H) */
 
diff --git a/src/or/circuitmux_ewma.h b/src/or/circuitmux_ewma.h
index 1f04408789..8f4e57865e 100644
--- a/src/or/circuitmux_ewma.h
+++ b/src/or/circuitmux_ewma.h
@@ -20,5 +20,5 @@ unsigned int cell_ewma_get_tick(void);
 void cell_ewma_set_scale_factor(const or_options_t *options,
                                 const networkstatus_t *consensus);
 
-#endif /* TOR_CIRCUITMUX_EWMA_H */
+#endif /* !defined(TOR_CIRCUITMUX_EWMA_H) */
 
diff --git a/src/or/circuitstats.c b/src/or/circuitstats.c
index 963892c9d1..ad0630e27e 100644
--- a/src/or/circuitstats.c
+++ b/src/or/circuitstats.c
@@ -60,7 +60,7 @@ static circuit_build_times_t circ_times;
 static int unit_tests = 0;
 #else
 #define unit_tests 0
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /** Return a pointer to the data structure describing our current circuit
  * build time history and computations. */
@@ -148,7 +148,7 @@ circuit_build_times_disabled_(const or_options_t *options,
                "Consensus=%d, Config=%d, AuthDir=%d, StateFile=%d",
                consensus_disabled, config_disabled, dirauth_disabled,
                state_disabled);
-#endif
+#endif /* 0 */
       return 1;
     } else {
 #if 0
@@ -157,7 +157,7 @@ circuit_build_times_disabled_(const or_options_t *options,
                 "Consensus=%d, Config=%d, AuthDir=%d, StateFile=%d",
                 consensus_disabled, config_disabled, dirauth_disabled,
                 state_disabled);
-#endif
+#endif /* 0 */
       return 0;
     }
   }
@@ -608,7 +608,7 @@ circuit_build_times_rewind_history(circuit_build_times_t *cbt, int n)
           "Rewound history by %d places. Current index: %d. "
           "Total: %d", n, cbt->build_times_idx, cbt->total_build_times);
 }
-#endif
+#endif /* 0 */
 
 /**
  * Add a new build time value <b>time</b> to the set of build times. Time
@@ -676,7 +676,7 @@ circuit_build_times_min(circuit_build_times_t *cbt)
   }
   return min_build_time;
 }
-#endif
+#endif /* 0 */
 
 /**
  * Calculate and return a histogram for the set of build times.
@@ -1165,7 +1165,7 @@ circuit_build_times_cdf(circuit_build_times_t *cbt, double x)
   tor_assert(0 <= ret && ret <= 1.0);
   return ret;
 }
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 #ifdef TOR_UNIT_TESTS
 /**
@@ -1200,7 +1200,7 @@ circuit_build_times_generate_sample(circuit_build_times_t *cbt,
   tor_assert(ret > 0);
   return ret;
 }
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 #ifdef TOR_UNIT_TESTS
 /**
@@ -1223,7 +1223,7 @@ circuit_build_times_initial_alpha(circuit_build_times_t *cbt,
     (tor_mathlog(cbt->Xm)-tor_mathlog(timeout_ms));
   tor_assert(cbt->alpha > 0);
 }
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /**
  * Returns true if we need circuits to be built
@@ -1682,7 +1682,7 @@ circuitbuild_running_unit_tests(void)
 {
   unit_tests = 1;
 }
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 void
 circuit_build_times_update_last_circ(circuit_build_times_t *cbt)
diff --git a/src/or/circuitstats.h b/src/or/circuitstats.h
index 8a1dec4bfd..92dc6405ba 100644
--- a/src/or/circuitstats.h
+++ b/src/or/circuitstats.h
@@ -54,7 +54,7 @@ STATIC void circuit_build_times_reset(circuit_build_times_t *cbt);
 /* Network liveness functions */
 STATIC int circuit_build_times_network_check_changed(
                                              circuit_build_times_t *cbt);
-#endif
+#endif /* defined(CIRCUITSTATS_PRIVATE) */
 
 #ifdef TOR_UNIT_TESTS
 build_time_t circuit_build_times_generate_sample(circuit_build_times_t *cbt,
@@ -63,7 +63,7 @@ double circuit_build_times_cdf(circuit_build_times_t *cbt, double x);
 void circuit_build_times_initial_alpha(circuit_build_times_t *cbt,
                                        double quantile, double time_ms);
 void circuitbuild_running_unit_tests(void);
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /* Network liveness functions */
 void circuit_build_times_network_is_live(circuit_build_times_t *cbt);
@@ -95,7 +95,7 @@ struct circuit_build_times_s {
   /** How long we wait before actually closing the circuit. */
   double close_ms;
 };
-#endif
+#endif /* defined(CIRCUITSTATS_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CIRCUITSTATS_H) */
 
diff --git a/src/or/circuituse.c b/src/or/circuituse.c
index 7545dea290..8ffb506043 100644
--- a/src/or/circuituse.c
+++ b/src/or/circuituse.c
@@ -410,7 +410,7 @@ circuit_conforms_to_options(const origin_circuit_t *circ,
 
   return 1;
 }
-#endif
+#endif /* 0 */
 
 /** Close all circuits that start at us, aren't open, and were born
  * at least CircuitBuildTimeout seconds ago.
@@ -634,7 +634,7 @@ circuit_expire_building(void)
                victim->n_circ_id,
                (int)(now - victim->timestamp_dirty));
     }
-#endif
+#endif /* 0 */
 
     /* if circ is !open, or if it's open but purpose is a non-finished
      * intro or rend, then mark it for close */
@@ -1339,7 +1339,7 @@ circuit_expire_old_circs_as_needed(time_t now)
       log_fn(LOG_INFO,"Creating a new testing circuit.");
       circuit_launch(CIRCUIT_PURPOSE_C_GENERAL, 0);
     }
-#endif
+#endif /* 0 */
   }
 }
 
@@ -2282,7 +2282,7 @@ circuit_get_open_circ_or_launch(entry_connection_t *conn,
          new_circ_purpose == CIRCUIT_PURPOSE_C_INTRODUCING)) {
       want_onehop = 1;
     }
-#endif
+#endif /* defined(ENABLE_TOR2WEB_MODE) */
 
     /* Determine what kind of a circuit to launch, and actually launch it. */
     {
diff --git a/src/or/circuituse.h b/src/or/circuituse.h
index 6c0bcbb357..2b0f983f1a 100644
--- a/src/or/circuituse.h
+++ b/src/or/circuituse.h
@@ -82,7 +82,7 @@ STATIC int needs_hs_client_circuits(time_t now,
 
 STATIC int needs_circuits_for_build(int num);
 
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
-#endif
+#endif /* !defined(TOR_CIRCUITUSE_H) */
 
diff --git a/src/or/command.c b/src/or/command.c
index 2c82984901..56134659c5 100644
--- a/src/or/command.c
+++ b/src/or/command.c
@@ -128,7 +128,7 @@ command_time_process_cell(cell_t *cell, channel_t *chan, int *time,
   }
   *time += time_passed;
 }
-#endif
+#endif /* defined(KEEP_TIMING_STATS) */
 
 /** Process a <b>cell</b> that was just received on <b>chan</b>. Keep internal
  * statistics about how many of each cell we've processed so far
@@ -165,7 +165,7 @@ command_process_cell(channel_t *chan, cell_t *cell)
     /* remember which second it is, for next time */
     current_second = now;
   }
-#endif
+#endif /* defined(KEEP_TIMING_STATS) */
 
 #ifdef KEEP_TIMING_STATS
 #define PROCESS_CELL(tp, cl, cn) STMT_BEGIN {                   \
@@ -173,9 +173,9 @@ command_process_cell(channel_t *chan, cell_t *cell)
     command_time_process_cell(cl, cn, & tp ## time ,            \
                               command_process_ ## tp ## _cell);  \
   } STMT_END
-#else
+#else /* !(defined(KEEP_TIMING_STATS)) */
 #define PROCESS_CELL(tp, cl, cn) command_process_ ## tp ## _cell(cl, cn)
-#endif
+#endif /* defined(KEEP_TIMING_STATS) */
 
   switch (cell->command) {
     case CELL_CREATE:
diff --git a/src/or/command.h b/src/or/command.h
index 5079d42e75..c0d1996cbb 100644
--- a/src/or/command.h
+++ b/src/or/command.h
@@ -27,5 +27,5 @@ extern uint64_t stats_n_created_cells_processed;
 extern uint64_t stats_n_relay_cells_processed;
 extern uint64_t stats_n_destroy_cells_processed;
 
-#endif
+#endif /* !defined(TOR_COMMAND_H) */
 
diff --git a/src/or/config.c b/src/or/config.c
index 93a0008987..af054bd87f 100644
--- a/src/or/config.c
+++ b/src/or/config.c
@@ -114,9 +114,9 @@
  * Coverity. Here's a kludge to unconfuse it.
  */
 #   define __INCLUDE_LEVEL__ 2
-#   endif
+#endif /* defined(__COVERITY__) && !defined(__INCLUDE_LEVEL__) */
 #include <systemd/sd-daemon.h>
-#endif
+#endif /* defined(HAVE_SYSTEMD) */
 
 /* Prefix used to indicate a Unix socket in a FooPort configuration. */
 static const char unix_socket_prefix[] = "unix:";
@@ -345,7 +345,7 @@ static config_var_t option_vars_[] = {
     SHARE_DATADIR PATH_SEPARATOR "tor" PATH_SEPARATOR "geoip"),
   V(GeoIPv6File,                 FILENAME,
     SHARE_DATADIR PATH_SEPARATOR "tor" PATH_SEPARATOR "geoip6"),
-#endif
+#endif /* defined(_WIN32) */
   OBSOLETE("Group"),
   V(GuardLifetime,               INTERVAL, "0 minutes"),
   V(HardwareAccel,               BOOL,     "0"),
@@ -1250,13 +1250,13 @@ options_act_reversible(const or_options_t *old_options, char **msg)
                       "on this OS/with this build.");
     goto rollback;
   }
-#else
+#else /* !(!defined(HAVE_SYS_UN_H)) */
   if (options->ControlSocketsGroupWritable && !options->ControlSocket) {
     *msg = tor_strdup("Setting ControlSocketGroupWritable without setting"
                       "a ControlSocket makes no sense.");
     goto rollback;
   }
-#endif
+#endif /* !defined(HAVE_SYS_UN_H) */
 
   if (running_tor) {
     int n_ports=0;
@@ -1333,7 +1333,7 @@ options_act_reversible(const or_options_t *old_options, char **msg)
       goto rollback;
     }
   }
-#endif
+#endif /* defined(HAVE_NET_IF_H) && defined(HAVE_NET_PFVAR_H) */
 
   /* Attempt to lock all current and future memory with mlockall() only once */
   if (options->DisableAllSwap) {
@@ -1385,7 +1385,7 @@ options_act_reversible(const or_options_t *old_options, char **msg)
                options->DataDirectory, strerror(errno));
     }
   }
-#endif
+#endif /* !defined(_WIN32) */
 
   /* Bail out at this point if we're not going to be a client or server:
    * we don't run Tor itself. */
@@ -1667,7 +1667,7 @@ options_act(const or_options_t *old_options)
     return -1;
   }
 /* LCOV_EXCL_STOP */
-#else
+#else /* !(defined(ENABLE_TOR2WEB_MODE)) */
   if (options->Tor2webMode) {
     log_err(LD_CONFIG, "This copy of Tor was not compiled to run in "
             "'tor2web mode'. It cannot be run with the Tor2webMode torrc "
@@ -1675,7 +1675,7 @@ options_act(const or_options_t *old_options)
             "--enable-tor2web-mode option.");
     return -1;
   }
-#endif
+#endif /* defined(ENABLE_TOR2WEB_MODE) */
 
   /* If we are a bridge with a pluggable transport proxy but no
      Extended ORPort, inform the user that they are missing out. */
@@ -2868,7 +2868,7 @@ options_validate_cb(void *old_options, void *options, void *default_options,
 #else
 #define COMPLAIN(args, ...)                                     \
   STMT_BEGIN log_warn(LD_CONFIG, args, ##__VA_ARGS__); STMT_END
-#endif
+#endif /* defined(__GNUC__) && __GNUC__ <= 3 */
 
 /** Log a warning message iff <b>filepath</b> is not absolute.
  * Warning message must contain option name <b>option</b> and
@@ -3171,7 +3171,7 @@ options_validate(or_options_t *old_options, or_options_t *options,
              "and OS X/Darwin-specific feature.");
 #else
       options->TransProxyType_parsed = TPT_PF_DIVERT;
-#endif
+#endif /* !defined(OpenBSD) && !defined( DARWIN ) */
     } else if (!strcasecmp(options->TransProxyType, "tproxy")) {
 #if !defined(__linux__)
       REJECT("TPROXY is a Linux-specific feature.");
@@ -3185,7 +3185,7 @@ options_validate(or_options_t *old_options, or_options_t *options,
              "and OS X/Darwin-specific feature.");
 #else
       options->TransProxyType_parsed = TPT_IPFW;
-#endif
+#endif /* !defined(KERNEL_MAY_SUPPORT_IPFW) */
     } else {
       REJECT("Unrecognized value for TransProxyType");
     }
@@ -3195,10 +3195,10 @@ options_validate(or_options_t *old_options, or_options_t *options,
       REJECT("Cannot use TransProxyType without any valid TransPort.");
     }
   }
-#else
+#else /* !(defined(USE_TRANSPARENT)) */
   if (options->TransPort_set)
     REJECT("TransPort is disabled in this build.");
-#endif
+#endif /* defined(USE_TRANSPARENT) */
 
   if (options->TokenBucketRefillInterval <= 0
       || options->TokenBucketRefillInterval > 1000) {
@@ -3519,7 +3519,7 @@ options_validate(or_options_t *old_options, or_options_t *options,
                "Tor2WebMode is enabled; disabling UseEntryGuards.");
     options->UseEntryGuards = 0;
   }
-#endif
+#endif /* defined(ENABLE_TOR2WEB_MODE) */
 
   if (options->Tor2webRendezvousPoints && !options->Tor2webMode) {
     REJECT("Tor2webRendezvousPoints cannot be set without Tor2webMode.");
@@ -4367,7 +4367,7 @@ compute_real_max_mem_in_queues(const uint64_t val, int log_guess)
 #else
       /* (presumably) 32-bit system. Let's hope for 1 GB. */
       result = ONE_GIGABYTE;
-#endif
+#endif /* SIZEOF_VOID_P >= 8 */
     } else {
       /* We detected it, so let's pick 3/4 of the total RAM as our limit. */
       const uint64_t avail = (ram / 4) * 3;
@@ -4700,7 +4700,7 @@ get_windows_conf_root(void)
   path[sizeof(path)-1] = '\0';
 #else
   strlcpy(path,tpath,sizeof(path));
-#endif
+#endif /* defined(UNICODE) */
 
   /* Now we need to free the memory that the path-idl was stored in.  In
    * typical Windows fashion, we can't just call 'free()' on it. */
@@ -4716,7 +4716,7 @@ get_windows_conf_root(void)
   is_set = 1;
   return path;
 }
-#endif
+#endif /* defined(_WIN32) */
 
 /** Return the default location for our torrc file (if <b>defaults_file</b> is
  * false), or for the torrc-defaults file (if <b>defaults_file</b> is true). */
@@ -4740,7 +4740,7 @@ get_default_conf_file(int defaults_file)
   }
 #else
   return defaults_file ? CONFDIR "/torrc-defaults" : CONFDIR "/torrc";
-#endif
+#endif /* defined(DISABLE_SYSTEM_TORRC) || ... */
 }
 
 /** Verify whether lst is a list of strings containing valid-looking
@@ -4891,9 +4891,9 @@ find_torrc_filename(config_line_t *cmd_arg,
       } else {
         fname = dflt ? tor_strdup(dflt) : NULL;
       }
-#else
+#else /* !(!defined(_WIN32)) */
       fname = dflt ? tor_strdup(dflt) : NULL;
-#endif
+#endif /* !defined(_WIN32) */
     }
   }
   return fname;
@@ -5524,7 +5524,7 @@ options_init_logs(const or_options_t *old_options, or_options_t *options,
       }
 #else
       log_warn(LD_CONFIG, "Syslog is not supported on this system. Sorry.");
-#endif
+#endif /* defined(HAVE_SYSLOG_H) */
       goto cleanup;
     }
 
@@ -6735,7 +6735,7 @@ parse_port_config(smartlist_t *out,
         } else if (!strcasecmp(elt, "AllAddrs")) {
 
           all_addrs = 1;
-#endif
+#endif /* 0 */
         } else if (!strcasecmp(elt, "IPv4Only")) {
           bind_ipv4_only = 1;
         } else if (!strcasecmp(elt, "IPv6Only")) {
@@ -7518,7 +7518,7 @@ normalize_data_directory(or_options_t *options)
   strlcpy(p,get_windows_conf_root(),MAX_PATH);
   options->DataDirectory = p;
   return 0;
-#else
+#else /* !(defined(_WIN32)) */
   const char *d = options->DataDirectory;
   if (!d)
     d = "~/.tor";
@@ -7544,7 +7544,7 @@ normalize_data_directory(or_options_t *options)
    options->DataDirectory = fn;
  }
  return 0;
-#endif
+#endif /* defined(_WIN32) */
 }
 
 /** Check and normalize the value of options->DataDirectory; return 0 if it
@@ -8075,10 +8075,10 @@ config_load_geoip_file_(sa_family_t family,
   }
   geoip_load_file(family, fname);
   tor_free(free_fname);
-#else
+#else /* !(defined(_WIN32)) */
   (void)default_fname;
   geoip_load_file(family, fname);
-#endif
+#endif /* defined(_WIN32) */
 }
 
 /** Load geoip files for IPv4 and IPv6 if <a>options</a> and
@@ -8153,9 +8153,9 @@ init_cookie_authentication(const char *fname, const char *header,
       log_warn(LD_FS,"Unable to make %s group-readable.", escaped(fname));
     }
   }
-#else
+#else /* !(!defined(_WIN32)) */
   (void) group_readable;
-#endif
+#endif /* !defined(_WIN32) */
 
   /* Success! */
   log_info(LD_GENERAL, "Generated auth cookie file in '%s'.", escaped(fname));
diff --git a/src/or/config.h b/src/or/config.h
index 3cfa7c4e5b..f69a3c483f 100644
--- a/src/or/config.h
+++ b/src/or/config.h
@@ -202,7 +202,7 @@ STATIC int parse_port_config(smartlist_t *out,
                   const char *defaultaddr,
                   int defaultport,
                   const unsigned flags);
-#endif
+#endif /* defined(CONFIG_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CONFIG_H) */
 
diff --git a/src/or/confparse.h b/src/or/confparse.h
index 9c4205d07c..9eb46fab03 100644
--- a/src/or/confparse.h
+++ b/src/or/confparse.h
@@ -129,5 +129,5 @@ const char *config_expand_abbrev(const config_format_t *fmt,
                                  int command_line, int warn_obsolete);
 void warn_deprecated_option(const char *what, const char *why);
 
-#endif
+#endif /* !defined(TOR_CONFPARSE_H) */
 
diff --git a/src/or/connection.c b/src/or/connection.c
index b831d231b0..1b979945bf 100644
--- a/src/or/connection.c
+++ b/src/or/connection.c
@@ -704,7 +704,7 @@ connection_free,(connection_t *conn))
     connection_ap_warn_and_unmark_if_pending_circ(TO_ENTRY_CONN(conn),
                                                   "connection_free");
   }
-#endif
+#endif /* 1 */
   connection_unregister_events(conn);
   connection_free_(conn);
 }
@@ -928,7 +928,7 @@ create_unix_sockaddr(const char *listenaddress, char **readable_address,
   *len_out = sizeof(struct sockaddr_un);
   return sockaddr;
 }
-#else
+#else /* !(defined(HAVE_SYS_UN_H) || defined(RUNNING_DOXYGEN)) */
 static struct sockaddr *
 create_unix_sockaddr(const char *listenaddress, char **readable_address,
                      socklen_t *len_out)
@@ -941,7 +941,7 @@ create_unix_sockaddr(const char *listenaddress, char **readable_address,
   tor_fragile_assert();
   return NULL;
 }
-#endif /* HAVE_SYS_UN_H */
+#endif /* defined(HAVE_SYS_UN_H) || defined(RUNNING_DOXYGEN) */
 
 /** Warn that an accept or a connect has failed because we're running out of
  * TCP sockets we can use on current system.  Rate-limit these warnings so
@@ -1056,7 +1056,7 @@ check_location_for_unix_socket(const or_options_t *options, const char *path,
   tor_free(p);
   return r;
 }
-#endif
+#endif /* defined(HAVE_SYS_UN_H) */
 
 /** Tell the TCP stack that it shouldn't wait for a long time after
  * <b>sock</b> has closed before reusing its port. Return 0 on success,
@@ -1079,7 +1079,7 @@ make_socket_reuseable(tor_socket_t sock)
     return -1;
   }
   return 0;
-#endif
+#endif /* defined(_WIN32) */
 }
 
 #ifdef _WIN32
@@ -1100,12 +1100,12 @@ make_win32_socket_exclusive(tor_socket_t sock)
     return -1;
   }
   return 0;
-#else
+#else /* !(defined(SO_EXCLUSIVEADDRUSE)) */
   (void) sock;
   return 0;
-#endif
+#endif /* defined(SO_EXCLUSIVEADDRUSE) */
 }
-#endif
+#endif /* defined(_WIN32) */
 
 /** Max backlog to pass to listen.  We start at */
 static int listen_limit = INT_MAX;
@@ -1195,7 +1195,7 @@ connection_listener_new(const struct sockaddr *listensockaddr,
                conn_type_to_string(type),
                tor_socket_strerror(errno));
     }
-#endif
+#endif /* defined(_WIN32) */
 
 #if defined(USE_TRANSPARENT) && defined(IP_TRANSPARENT)
     if (options->TransProxyType_parsed == TPT_TPROXY &&
@@ -1212,7 +1212,7 @@ connection_listener_new(const struct sockaddr *listensockaddr,
                  tor_socket_strerror(e), extra);
       }
     }
-#endif
+#endif /* defined(USE_TRANSPARENT) && defined(IP_TRANSPARENT) */
 
 #ifdef IPV6_V6ONLY
     if (listensockaddr->sa_family == AF_INET6) {
@@ -1227,7 +1227,7 @@ connection_listener_new(const struct sockaddr *listensockaddr,
         /* Keep going; probably not harmful. */
       }
     }
-#endif
+#endif /* defined(IPV6_V6ONLY) */
 
     if (bind(s,listensockaddr,socklen) < 0) {
       const char *helpfulhint = "";
@@ -1330,7 +1330,7 @@ connection_listener_new(const struct sockaddr *listensockaddr,
         goto err;
       }
     }
-#endif
+#endif /* defined(HAVE_PWD_H) */
 
     {
       unsigned mode;
@@ -1361,7 +1361,7 @@ connection_listener_new(const struct sockaddr *listensockaddr,
                tor_socket_strerror(tor_socket_errno(s)));
       goto err;
     }
-#endif /* HAVE_SYS_UN_H */
+#endif /* defined(HAVE_SYS_UN_H) */
   } else {
     log_err(LD_BUG, "Got unexpected address family %d.",
             listensockaddr->sa_family);
@@ -2626,7 +2626,7 @@ retry_listener_ports(smartlist_t *old_conns,
     if (port->is_unix_addr && !geteuid() && (options->User) &&
         strcmp(options->User, "root"))
       continue;
-#endif
+#endif /* !defined(_WIN32) */
 
     if (port->is_unix_addr) {
       listensockaddr = (struct sockaddr *)
diff --git a/src/or/connection.h b/src/or/connection.h
index 5b51bb9fae..4a5bd6971b 100644
--- a/src/or/connection.h
+++ b/src/or/connection.h
@@ -286,7 +286,7 @@ MOCK_DECL(STATIC int,connection_connect_sockaddr,
 MOCK_DECL(STATIC void, kill_conn_list_for_oos, (smartlist_t *conns));
 MOCK_DECL(STATIC smartlist_t *, pick_oos_victims, (int n));
 
-#endif
+#endif /* defined(CONNECTION_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CONNECTION_H) */
 
diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c
index 8bb2af3226..e413e5bc36 100644
--- a/src/or/connection_edge.c
+++ b/src/or/connection_edge.c
@@ -115,7 +115,7 @@
 #define TRANS_NETFILTER
 #define TRANS_NETFILTER_IPV6
 #endif
-#endif
+#endif /* defined(HAVE_LINUX_NETFILTER_IPV6_IP6_TABLES_H) */
 
 #if defined(HAVE_NET_IF_H) && defined(HAVE_NET_PFVAR_H)
 #include <net/if.h>
@@ -661,7 +661,7 @@ connection_ap_about_to_close(entry_connection_t *entry_conn)
     connection_ap_warn_and_unmark_if_pending_circ(entry_conn,
                                                   "about_to_close");
   }
-#endif
+#endif /* 1 */
 
   control_event_stream_bandwidth(edge_conn);
   control_event_stream_status(entry_conn, STREAM_EVENT_CLOSED,
@@ -871,9 +871,9 @@ connection_ap_rescan_and_attach_pending(void)
     entry_conn->marked_pending_circ_line = 0;   \
     entry_conn->marked_pending_circ_file = 0;   \
   } while (0)
-#else
+#else /* !(defined(DEBUGGING_17659)) */
 #define UNMARK() do { } while (0)
-#endif
+#endif /* defined(DEBUGGING_17659) */
 
 /** Tell any AP streams that are listed as waiting for a new circuit to try
  * again.  If there is an available circuit for a stream, attach it. Otherwise,
@@ -979,7 +979,7 @@ connection_ap_mark_as_pending_circuit_(entry_connection_t *entry_conn,
     log_warn(LD_BUG, "(Previously called from %s:%d.)\n",
              f2 ? f2 : "<NULL>",
              entry_conn->marked_pending_circ_line);
-#endif
+#endif /* defined(DEBUGGING_17659) */
     log_backtrace(LOG_WARN, LD_BUG, "To debug, this may help");
     return;
   }
@@ -1791,7 +1791,7 @@ connection_ap_handshake_rewrite_and_attach(entry_connection_t *conn,
       connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
       return -1;
     }
-#endif
+#endif /* defined(ENABLE_TOR2WEB_MODE) */
 
     /* socks->address is a non-onion hostname or IP address.
      * If we can't do any non-onion requests, refuse the connection.
@@ -2067,7 +2067,7 @@ get_pf_socket(void)
 #else
   /* works on NetBSD and FreeBSD */
   pf = tor_open_cloexec("/dev/pf", O_RDWR, 0);
-#endif
+#endif /* defined(OpenBSD) */
 
   if (pf < 0) {
     log_warn(LD_NET, "open(\"/dev/pf\") failed: %s", strerror(errno));
@@ -2077,7 +2077,7 @@ get_pf_socket(void)
   pf_socket = pf;
   return pf_socket;
 }
-#endif
+#endif /* defined(TRANS_PF) */
 
 #if defined(TRANS_NETFILTER) || defined(TRANS_PF) || \
   defined(TRANS_TPROXY)
@@ -2100,7 +2100,7 @@ destination_from_socket(entry_connection_t *conn, socks_request_t *req)
     }
     goto done;
   }
-#endif
+#endif /* defined(TRANS_TPROXY) */
 
 #ifdef TRANS_NETFILTER
   int rv = -1;
@@ -2110,13 +2110,13 @@ destination_from_socket(entry_connection_t *conn, socks_request_t *req)
       rv = getsockopt(ENTRY_TO_CONN(conn)->s, SOL_IP, SO_ORIGINAL_DST,
                   (struct sockaddr*)&orig_dst, &orig_dst_len);
       break;
-#endif
+#endif /* defined(TRANS_NETFILTER_IPV4) */
 #ifdef TRANS_NETFILTER_IPV6
     case AF_INET6:
       rv = getsockopt(ENTRY_TO_CONN(conn)->s, SOL_IPV6, IP6T_SO_ORIGINAL_DST,
                   (struct sockaddr*)&orig_dst, &orig_dst_len);
       break;
-#endif
+#endif /* defined(TRANS_NETFILTER_IPV6) */
     default:
       log_warn(LD_BUG,
                "Received transparent data from an unsuported socket family %d",
@@ -2142,7 +2142,7 @@ destination_from_socket(entry_connection_t *conn, socks_request_t *req)
   (void)req;
   log_warn(LD_BUG, "Unable to determine destination from socket.");
   return -1;
-#endif
+#endif /* defined(TRANS_NETFILTER) || ... */
 
  done:
   tor_addr_from_sockaddr(&addr, (struct sockaddr*)&orig_dst, &req->port);
@@ -2150,7 +2150,7 @@ destination_from_socket(entry_connection_t *conn, socks_request_t *req)
 
   return 0;
 }
-#endif
+#endif /* defined(TRANS_NETFILTER) || defined(TRANS_PF) || ... */
 
 #ifdef TRANS_PF
 static int
@@ -2184,7 +2184,7 @@ destination_from_pf(entry_connection_t *conn, socks_request_t *req)
 
     return 0;
   }
-#endif
+#endif /* defined(__FreeBSD__) */
 
   memset(&pnl, 0, sizeof(pnl));
   pnl.proto           = IPPROTO_TCP;
@@ -2233,7 +2233,7 @@ destination_from_pf(entry_connection_t *conn, socks_request_t *req)
 
   return 0;
 }
-#endif
+#endif /* defined(TRANS_PF) */
 
 /** Fetch the original destination address and port from a
  * system-specific interface and put them into a
@@ -2269,7 +2269,7 @@ connection_ap_get_original_destination(entry_connection_t *conn,
   log_warn(LD_BUG, "Called connection_ap_get_original_destination, but no "
            "transparent proxy method was configured.");
   return -1;
-#endif
+#endif /* defined(TRANS_NETFILTER) || ... */
 }
 
 /** connection_edge_process_inbuf() found a conn in state
diff --git a/src/or/connection_edge.h b/src/or/connection_edge.h
index e47043f7fe..c6583d3845 100644
--- a/src/or/connection_edge.h
+++ b/src/or/connection_edge.h
@@ -191,7 +191,7 @@ STATIC void connection_ap_handshake_rewrite(entry_connection_t *conn,
                                             rewrite_result_t *out);
 
 STATIC int connection_ap_process_http_connect(entry_connection_t *conn);
-#endif
+#endif /* defined(CONNECTION_EDGE_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CONNECTION_EDGE_H) */
 
diff --git a/src/or/connection_or.h b/src/or/connection_or.h
index fe85a3f5fd..ee66b7c528 100644
--- a/src/or/connection_or.h
+++ b/src/or/connection_or.h
@@ -118,5 +118,5 @@ void connection_or_group_set_badness_(smartlist_t *group, int force);
 extern int certs_cell_ed25519_disabled_for_testing;
 #endif
 
-#endif
+#endif /* !defined(TOR_CONNECTION_OR_H) */
 
diff --git a/src/or/conscache.c b/src/or/conscache.c
index 9e13ce8e43..0f3e453eaf 100644
--- a/src/or/conscache.c
+++ b/src/or/conscache.c
@@ -15,7 +15,7 @@
  * changes throughout our logic.
  */
 #define MUST_UNMAP_TO_UNLINK
-#endif
+#endif /* defined(_WIN32) */
 
 /**
  * A consensus_cache_entry_t is a reference-counted handle to an
@@ -90,11 +90,11 @@ consensus_cache_open(const char *subdir, int max_entries)
    */
 #define VERY_LARGE_STORAGEDIR_LIMIT (1000*1000)
   storagedir_max_entries = VERY_LARGE_STORAGEDIR_LIMIT;
-#else
+#else /* !(defined(MUST_UNMAP_TO_UNLINK)) */
   /* Otherwise, we can just tell the storagedir to use the same limits
    * as this cache. */
   storagedir_max_entries = max_entries;
-#endif
+#endif /* defined(MUST_UNMAP_TO_UNLINK) */
 
   cache->dir = storage_dir_new(directory, storagedir_max_entries);
   tor_free(directory);
@@ -145,7 +145,7 @@ consensus_cache_register_with_sandbox(consensus_cache_t *cache,
    * conditional.
    */
   tor_assert_nonfatal_unreached();
-#endif
+#endif /* defined(MUST_UNMAP_TO_UNLINK) */
   return storage_dir_register_with_sandbox(cache->dir, cfg);
 }
 
@@ -474,7 +474,7 @@ consensus_cache_get_n_filenames_available(consensus_cache_t *cache)
     return 0;
 #else
   tor_assert_nonfatal(max >= used);
-#endif
+#endif /* defined(MUST_UNMAP_TO_UNLINK) */
   return max - used;
 }
 
@@ -495,7 +495,7 @@ consensus_cache_delete_pending(consensus_cache_t *cache, int force)
     if (ent->map) {
       force_ent = 0;
     }
-#endif
+#endif /* defined(MUST_UNMAP_TO_UNLINK) */
     if (! force_ent) {
       if (ent->refcnt > 1 || BUG(ent->in_cache == NULL)) {
         /* Somebody is using this entry right now */
@@ -611,5 +611,5 @@ consensus_cache_entry_is_mapped(consensus_cache_entry_t *ent)
     return 0;
   }
 }
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
diff --git a/src/or/conscache.h b/src/or/conscache.h
index a0d74c4e08..3c89dedf43 100644
--- a/src/or/conscache.h
+++ b/src/or/conscache.h
@@ -58,5 +58,5 @@ int consensus_cache_entry_get_body(const consensus_cache_entry_t *ent,
 int consensus_cache_entry_is_mapped(consensus_cache_entry_t *ent);
 #endif
 
-#endif
+#endif /* !defined(TOR_CONSCACHE_H) */
 
diff --git a/src/or/consdiff.h b/src/or/consdiff.h
index d05df74b75..eb772c0b2b 100644
--- a/src/or/consdiff.h
+++ b/src/or/consdiff.h
@@ -92,7 +92,7 @@ MOCK_DECL(STATIC int,
 MOCK_DECL(STATIC int,
           consensus_digest_eq,(const uint8_t *d1,
                                const uint8_t *d2));
-#endif
+#endif /* defined(CONSDIFF_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CONSDIFF_H) */
 
diff --git a/src/or/consdiffmgr.c b/src/or/consdiffmgr.c
index 831d5d45c3..1d63d59577 100644
--- a/src/or/consdiffmgr.c
+++ b/src/or/consdiffmgr.c
@@ -659,7 +659,7 @@ consdiffmgr_find_diff_from(consensus_cache_entry_t **entry_out,
   smartlist_free(matches);
 
   return result;
-#endif
+#endif /* 0 */
 }
 
 /**
diff --git a/src/or/consdiffmgr.h b/src/or/consdiffmgr.h
index 079f9fe2d2..df569c8e23 100644
--- a/src/or/consdiffmgr.h
+++ b/src/or/consdiffmgr.h
@@ -68,7 +68,7 @@ STATIC int cdm_entry_get_sha3_value(uint8_t *digest_out,
                                     const char *label);
 STATIC int uncompress_or_copy(char **out, size_t *outlen,
                               consensus_cache_entry_t *ent);
-#endif
+#endif /* defined(CONSDIFFMGR_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CONSDIFFMGR_H) */
 
diff --git a/src/or/control.c b/src/or/control.c
index c815502aa4..bd5f01a046 100644
--- a/src/or/control.c
+++ b/src/or/control.c
@@ -593,7 +593,7 @@ control_ports_write_to_file(void)
       smartlist_add_asprintf(lines, "UNIX_PORT=%s\n", conn->address);
       continue;
     }
-#endif
+#endif /* defined(AF_UNIX) */
     smartlist_add_asprintf(lines, "PORT=%s:%d\n", conn->address, conn->port);
   } SMARTLIST_FOREACH_END(conn);
 
@@ -610,7 +610,7 @@ control_ports_write_to_file(void)
                options->ControlPortWriteToFile);
     }
   }
-#endif
+#endif /* !defined(_WIN32) */
   tor_free(joined);
   SMARTLIST_FOREACH(lines, char *, cp, tor_free(cp));
   smartlist_free(lines);
@@ -1749,7 +1749,7 @@ getinfo_helper_misc(control_connection_t *conn, const char *question,
     #else
       int myUid = geteuid();
       tor_asprintf(answer, "%d", myUid);
-    #endif
+#endif /* defined(_WIN32) */
   } else if (!strcmp(question, "process/user")) {
     #ifdef _WIN32
       *answer = tor_strdup("");
@@ -1762,7 +1762,7 @@ getinfo_helper_misc(control_connection_t *conn, const char *question,
       } else {
         *answer = tor_strdup("");
       }
-    #endif
+#endif /* defined(_WIN32) */
   } else if (!strcmp(question, "process/descriptor-limit")) {
     int max_fds = get_max_sockets();
     tor_asprintf(answer, "%d", max_fds);
@@ -7317,5 +7317,5 @@ control_testing_set_global_event_mask(uint64_t mask)
 {
   global_event_mask = mask;
 }
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
diff --git a/src/or/control.h b/src/or/control.h
index 8003126f3e..e957b593a6 100644
--- a/src/or/control.h
+++ b/src/or/control.h
@@ -225,7 +225,7 @@ MOCK_DECL(STATIC void,
           queue_control_event_string,(uint16_t event, char *msg));
 
 void control_testing_set_global_event_mask(uint64_t mask);
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /** Helper structure: temporarily stores cell statistics for a circuit. */
 typedef struct cell_stats_t {
@@ -292,7 +292,7 @@ STATIC int getinfo_helper_dir(
     const char *question, char **answer,
     const char **errmsg);
 
-#endif
+#endif /* defined(CONTROL_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_CONTROL_H) */
 
diff --git a/src/or/cpuworker.h b/src/or/cpuworker.h
index 320de9532f..d39851325f 100644
--- a/src/or/cpuworker.h
+++ b/src/or/cpuworker.h
@@ -33,5 +33,5 @@ void cpuworker_log_onionskin_overhead(int severity, int onionskin_type,
                                       const char *onionskin_type_name);
 void cpuworker_cancel_circ_handshake(or_circuit_t *circ);
 
-#endif
+#endif /* !defined(TOR_CPUWORKER_H) */
 
diff --git a/src/or/dircollate.h b/src/or/dircollate.h
index 52214282b9..7932e18998 100644
--- a/src/or/dircollate.h
+++ b/src/or/dircollate.h
@@ -62,7 +62,7 @@ struct dircollator_s {
    * identity digests .*/
   smartlist_t *all_rsa_sha1_lst;
 };
-#endif
+#endif /* defined(DIRCOLLATE_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_DIRCOLLATE_H) */
 
diff --git a/src/or/directory.h b/src/or/directory.h
index 1200728411..79984be32d 100644
--- a/src/or/directory.h
+++ b/src/or/directory.h
@@ -194,7 +194,7 @@ STATIC void warn_disallowed_anonymous_compression_method(compress_method_t);
 STATIC int handle_response_fetch_hsdesc_v3(dir_connection_t *conn,
                                           const response_handler_args_t *args);
 
-#endif
+#endif /* defined(DIRECTORY_PRIVATE) */
 
 #ifdef TOR_UNIT_TESTS
 /* Used only by test_dir.c and test_hs_cache.c */
@@ -232,7 +232,7 @@ STATIC int parse_hs_version_from_post(const char *url, const char *prefix,
                                       const char **end_pos);
 
 STATIC unsigned parse_accept_encoding_header(const char *h);
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 #if defined(TOR_UNIT_TESTS) || defined(DIRECTORY_PRIVATE)
 /* Used only by directory.c and test_dir.c */
@@ -242,7 +242,7 @@ STATIC unsigned parse_accept_encoding_header(const char *h);
 /* no more than triple the previous delay */
 #define DIR_TEST_NET_RANDOM_MULTIPLIER (2)
 
-#endif
+#endif /* defined(TOR_UNIT_TESTS) || defined(DIRECTORY_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_DIRECTORY_H) */
 
diff --git a/src/or/dirserv.c b/src/or/dirserv.c
index 06ac15d587..ddee92da55 100644
--- a/src/or/dirserv.c
+++ b/src/or/dirserv.c
@@ -338,7 +338,7 @@ dirserv_router_get_status(const routerinfo_t *router, const char **msg,
         }
         return FP_REJECT;
       }
-#endif
+#endif /* defined(DISABLE_DISABLING_ED25519) */
     }
   }
 
diff --git a/src/or/dirserv.h b/src/or/dirserv.h
index 480174d5bb..46967a6cb2 100644
--- a/src/or/dirserv.h
+++ b/src/or/dirserv.h
@@ -182,7 +182,7 @@ STATIC int dirserv_has_measured_bw(const char *node_id);
 STATIC int
 dirserv_read_guardfraction_file_from_str(const char *guardfraction_file_str,
                                       smartlist_t *vote_routerstatuses);
-#endif
+#endif /* defined(DIRSERV_PRIVATE) */
 
 int dirserv_read_measured_bandwidths(const char *from_file,
                                      smartlist_t *routerstatuses);
@@ -204,5 +204,5 @@ void dirserv_spool_remove_missing_and_guess_size(dir_connection_t *conn,
 void dirserv_spool_sort(dir_connection_t *conn);
 void dir_conn_clear_spool(dir_connection_t *conn);
 
-#endif
+#endif /* !defined(TOR_DIRSERV_H) */
 
diff --git a/src/or/dirvote.h b/src/or/dirvote.h
index e342dc78ea..fb3e60f000 100644
--- a/src/or/dirvote.h
+++ b/src/or/dirvote.h
@@ -242,7 +242,7 @@ STATIC int
 networkstatus_compute_bw_weights_v10(smartlist_t *chunks, int64_t G,
                                      int64_t M, int64_t E, int64_t D,
                                      int64_t T, int64_t weight_scale);
-#endif
+#endif /* defined(DIRVOTE_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_DIRVOTE_H) */
 
diff --git a/src/or/dns.c b/src/or/dns.c
index 2d642773f3..078bde3ef2 100644
--- a/src/or/dns.c
+++ b/src/or/dns.c
@@ -102,7 +102,7 @@ static void assert_cache_ok_(void);
 #define assert_cache_ok() assert_cache_ok_()
 #else
 #define assert_cache_ok() STMT_NIL
-#endif
+#endif /* defined(DEBUG_DNS_CACHE) */
 static void assert_resolve_ok(cached_resolve_t *resolve);
 
 /** Hash table of cached_resolve objects. */
@@ -961,14 +961,14 @@ assert_connection_edge_not_dns_pending(edge_connection_t *conn)
   for (pend = resolve->pending_connections; pend; pend = pend->next) {
     tor_assert(pend->conn != conn);
   }
-#else
+#else /* !(1) */
   cached_resolve_t **resolve;
   HT_FOREACH(resolve, cache_map, &cache_root) {
     for (pend = (*resolve)->pending_connections; pend; pend = pend->next) {
       tor_assert(pend->conn != conn);
     }
   }
-#endif
+#endif /* 1 */
 }
 
 /** Log an error and abort if any connection waiting for a DNS resolve is
@@ -1396,7 +1396,7 @@ configure_nameservers(int force)
       evdns_base_load_hosts(the_evdns_base,
           sandbox_intern_string("/etc/hosts"));
     }
-#endif
+#endif /* defined(DNS_OPTION_HOSTSFILE) && defined(USE_LIBSECCOMP) */
     log_info(LD_EXIT, "Parsing resolver configuration in '%s'", conf_fname);
     if ((r = evdns_base_resolv_conf_parse(the_evdns_base, flags,
         sandbox_intern_string(conf_fname)))) {
@@ -1434,7 +1434,7 @@ configure_nameservers(int force)
     tor_free(resolv_conf_fname);
     resolv_conf_mtime = 0;
   }
-#endif
+#endif /* defined(_WIN32) */
 
 #define SET(k,v)  evdns_base_set_option(the_evdns_base, (k), (v))
 
@@ -2033,7 +2033,7 @@ assert_resolve_ok(cached_resolve_t *resolve)
       tor_assert(!resolve->hostname);
     else
       tor_assert(!resolve->result_ipv4.addr_ipv4);
-#endif
+#endif /* 0 */
     /*XXXXX ADD MORE */
   }
 }
@@ -2097,7 +2097,7 @@ assert_cache_ok_(void)
     });
 }
 
-#endif
+#endif /* defined(DEBUG_DNS_CACHE) */
 
 cached_resolve_t *
 dns_get_cache_entry(cached_resolve_t *query)
diff --git a/src/or/dns.h b/src/or/dns.h
index a81cbd20da..28d9f947b4 100644
--- a/src/or/dns.h
+++ b/src/or/dns.h
@@ -64,7 +64,7 @@ set_exitconn_info_from_resolve,(edge_connection_t *exitconn,
 MOCK_DECL(STATIC int,
 launch_resolve,(cached_resolve_t *resolve));
 
-#endif
+#endif /* defined(DNS_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_DNS_H) */
 
diff --git a/src/or/dns_structs.h b/src/or/dns_structs.h
index dc00e9f7b9..e22f23ac15 100644
--- a/src/or/dns_structs.h
+++ b/src/or/dns_structs.h
@@ -98,5 +98,5 @@ typedef struct cached_resolve_t {
   int minheap_idx;
 } cached_resolve_t;
 
-#endif
+#endif /* !defined(TOR_DNS_STRUCTS_H) */
 
diff --git a/src/or/dnsserv.c b/src/or/dnsserv.c
index 54a22a5150..d254717a54 100644
--- a/src/or/dnsserv.c
+++ b/src/or/dnsserv.c
@@ -226,10 +226,10 @@ dnsserv_launch_request(const char *name, int reverse,
     TO_CONN(conn)->port = control_conn->base_.port;
     TO_CONN(conn)->address = tor_addr_to_str_dup(&control_conn->base_.addr);
   }
-#else
+#else /* !(defined(AF_UNIX)) */
   TO_CONN(conn)->port = control_conn->base_.port;
   TO_CONN(conn)->address = tor_addr_to_str_dup(&control_conn->base_.addr);
-#endif
+#endif /* defined(AF_UNIX) */
 
   if (reverse)
     entry_conn->socks_request->command = SOCKS_COMMAND_RESOLVE_PTR;
diff --git a/src/or/dnsserv.h b/src/or/dnsserv.h
index 6c0643b8dc..2af366eee5 100644
--- a/src/or/dnsserv.h
+++ b/src/or/dnsserv.h
@@ -23,5 +23,5 @@ void dnsserv_reject_request(entry_connection_t *conn);
 int dnsserv_launch_request(const char *name, int is_reverse,
                            control_connection_t *control_conn);
 
-#endif
+#endif /* !defined(TOR_DNSSERV_H) */
 
diff --git a/src/or/entrynodes.c b/src/or/entrynodes.c
index c104b8a973..129b983334 100644
--- a/src/or/entrynodes.c
+++ b/src/or/entrynodes.c
@@ -1751,7 +1751,7 @@ entry_guards_update_primary(guard_selection_t *gs)
                    bool_eq(guard->is_primary,
                            smartlist_contains(new_primary_guards, guard)));
   });
-#endif
+#endif /* 1 */
 
   int any_change = 0;
   if (smartlist_len(gs->primary_entry_guards) !=
diff --git a/src/or/entrynodes.h b/src/or/entrynodes.h
index 735c7738ba..f74ccd97f4 100644
--- a/src/or/entrynodes.h
+++ b/src/or/entrynodes.h
@@ -310,7 +310,7 @@ struct circuit_guard_state_t {
    */
   entry_guard_restriction_t *restrictions;
 };
-#endif
+#endif /* defined(ENTRYNODES_PRIVATE) */
 
 /* Common entry points for old and new guard code */
 int guards_update_all(void);
@@ -335,7 +335,7 @@ int num_live_entry_guards_for_guard_selection(
     guard_selection_t *gs,
     int for_directory);
 int num_live_entry_guards(int for_directory);
-#endif
+#endif /* 1 */
 
 const node_t *entry_guard_find_node(const entry_guard_t *guard);
 const char *entry_guard_get_rsa_id_digest(const entry_guard_t *guard);
@@ -550,7 +550,7 @@ STATIC unsigned entry_guards_note_guard_success(guard_selection_t *gs,
                                                 unsigned old_state);
 STATIC int entry_guard_has_higher_priority(entry_guard_t *a, entry_guard_t *b);
 STATIC char *getinfo_helper_format_single_entry_guard(const entry_guard_t *e);
-#endif
+#endif /* defined(ENTRYNODES_PRIVATE) */
 
 void remove_all_entry_guards_for_guard_selection(guard_selection_t *gs);
 void remove_all_entry_guards(void);
@@ -597,5 +597,5 @@ guard_get_guardfraction_bandwidth(guardfraction_bandwidth_t *guardfraction_bw,
                                   int orig_bandwidth,
                                   uint32_t guardfraction_percentage);
 
-#endif
+#endif /* !defined(TOR_ENTRYNODES_H) */
 
diff --git a/src/or/ext_orport.h b/src/or/ext_orport.h
index b2cd05db8f..af2b97e77c 100644
--- a/src/or/ext_orport.h
+++ b/src/or/ext_orport.h
@@ -36,7 +36,7 @@ STATIC int handle_client_auth_nonce(const char *client_nonce,
 extern uint8_t *ext_or_auth_cookie;
 extern int ext_or_auth_cookie_is_set;
 #endif
-#endif
+#endif /* defined(EXT_ORPORT_PRIVATE) */
 
-#endif
+#endif /* !defined(EXT_ORPORT_H) */
 
diff --git a/src/or/fp_pair.h b/src/or/fp_pair.h
index 4cea3eda6d..f7c060b459 100644
--- a/src/or/fp_pair.h
+++ b/src/or/fp_pair.h
@@ -41,5 +41,5 @@ void fp_pair_map_assert_ok(const fp_pair_map_t *map);
 
 #undef DECLARE_MAP_FNS
 
-#endif
+#endif /* !defined(_TOR_FP_PAIR_H) */
 
diff --git a/src/or/geoip.h b/src/or/geoip.h
index 55ca8ca28c..acf61b97ae 100644
--- a/src/or/geoip.h
+++ b/src/or/geoip.h
@@ -19,7 +19,7 @@ STATIC int geoip_parse_entry(const char *line, sa_family_t family);
 STATIC int geoip_get_country_by_ipv4(uint32_t ipaddr);
 STATIC int geoip_get_country_by_ipv6(const struct in6_addr *addr);
 STATIC void clear_geoip_db(void);
-#endif
+#endif /* defined(GEOIP_PRIVATE) */
 int should_record_bridge_info(const or_options_t *options);
 int geoip_load_file(sa_family_t family, const char *filename);
 MOCK_DECL(int, geoip_get_country_by_addr, (const tor_addr_t *addr));
@@ -67,5 +67,5 @@ const char *geoip_get_bridge_stats_extrainfo(time_t);
 char *geoip_get_bridge_stats_controller(time_t);
 char *format_client_stats_heartbeat(time_t now);
 
-#endif
+#endif /* !defined(TOR_GEOIP_H) */
 
diff --git a/src/or/hibernate.c b/src/or/hibernate.c
index 8c48a6f47d..74ab766468 100644
--- a/src/or/hibernate.c
+++ b/src/or/hibernate.c
@@ -1124,5 +1124,5 @@ hibernate_set_state_for_testing_(hibernate_state_t newstate)
 {
   hibernate_state = newstate;
 }
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
diff --git a/src/or/hibernate.h b/src/or/hibernate.h
index 8bdb65a927..85fb42864b 100644
--- a/src/or/hibernate.h
+++ b/src/or/hibernate.h
@@ -53,7 +53,7 @@ typedef enum {
 #ifdef TOR_UNIT_TESTS
 void hibernate_set_state_for_testing_(hibernate_state_t newstate);
 #endif
-#endif
+#endif /* defined(HIBERNATE_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_HIBERNATE_H) */
 
diff --git a/src/or/hs_cache.h b/src/or/hs_cache.h
index a6beaebc10..2dcc518a71 100644
--- a/src/or/hs_cache.h
+++ b/src/or/hs_cache.h
@@ -121,7 +121,7 @@ STATIC size_t cache_clean_v3_as_dir(time_t now, time_t global_cutoff);
 STATIC hs_cache_client_descriptor_t *
 lookup_v3_desc_as_client(const uint8_t *key);
 
-#endif /* HS_CACHE_PRIVATE */
+#endif /* defined(HS_CACHE_PRIVATE) */
 
-#endif /* TOR_HS_CACHE_H */
+#endif /* !defined(TOR_HS_CACHE_H) */
 
diff --git a/src/or/hs_cell.h b/src/or/hs_cell.h
index 5136fce933..958dde4ffc 100644
--- a/src/or/hs_cell.h
+++ b/src/or/hs_cell.h
@@ -118,5 +118,5 @@ int hs_cell_parse_rendezvous2(const uint8_t *payload, size_t payload_len,
 /* Util API. */
 void hs_cell_introduce1_data_clear(hs_cell_introduce1_data_t *data);
 
-#endif /* TOR_HS_CELL_H */
+#endif /* !defined(TOR_HS_CELL_H) */
 
diff --git a/src/or/hs_circuit.h b/src/or/hs_circuit.h
index 3b0e3aca1c..9085e3fb0b 100644
--- a/src/or/hs_circuit.h
+++ b/src/or/hs_circuit.h
@@ -59,5 +59,5 @@ int hs_circuit_setup_e2e_rend_circ(origin_circuit_t *circ,
 int hs_circuit_setup_e2e_rend_circ_legacy_client(origin_circuit_t *circ,
                                           const uint8_t *rend_cell_body);
 
-#endif /* TOR_HS_CIRCUIT_H */
+#endif /* !defined(TOR_HS_CIRCUIT_H) */
 
diff --git a/src/or/hs_circuitmap.c b/src/or/hs_circuitmap.c
index 63d5c1ba2e..97d6053e9b 100644
--- a/src/or/hs_circuitmap.c
+++ b/src/or/hs_circuitmap.c
@@ -87,7 +87,7 @@ get_hs_circuitmap(void)
   return the_hs_circuitmap;
 }
 
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /****************** HS circuitmap utility functions **************************/
 
diff --git a/src/or/hs_circuitmap.h b/src/or/hs_circuitmap.h
index 0903de2347..43b2947c17 100644
--- a/src/or/hs_circuitmap.h
+++ b/src/or/hs_circuitmap.h
@@ -99,7 +99,7 @@ struct hs_token_s {
   uint8_t *token;
 };
 
-#endif /* HS_CIRCUITMAP_PRIVATE */
+#endif /* defined(HS_CIRCUITMAP_PRIVATE) */
 
 #ifdef TOR_UNIT_TESTS
 
@@ -107,5 +107,5 @@ hs_circuitmap_ht *get_hs_circuitmap(void);
 
 #endif /* TOR_UNIT_TESTS */
 
-#endif /* TOR_HS_CIRCUITMAP_H */
+#endif /* !defined(TOR_HS_CIRCUITMAP_H) */
 
diff --git a/src/or/hs_client.h b/src/or/hs_client.h
index d50d346217..4eee1174bd 100644
--- a/src/or/hs_client.h
+++ b/src/or/hs_client.h
@@ -77,7 +77,7 @@ client_get_random_intro(const ed25519_public_key_t *service_pk);
 STATIC extend_info_t *
 desc_intro_point_to_extend_info(const hs_desc_intro_point_t *ip);
 
-#endif /* HS_CLIENT_PRIVATE */
+#endif /* defined(HS_CLIENT_PRIVATE) */
 
-#endif /* TOR_HS_CLIENT_H */
+#endif /* !defined(TOR_HS_CLIENT_H) */
 
diff --git a/src/or/hs_common.c b/src/or/hs_common.c
index 6fe6b82f5e..2cdfe57cd6 100644
--- a/src/or/hs_common.c
+++ b/src/or/hs_common.c
@@ -76,7 +76,7 @@ set_unix_port(edge_connection_t *conn, rend_service_port_config_t *p)
   return 0;
 }
 
-#else /* defined(HAVE_SYS_UN_H) */
+#else /* !(defined(HAVE_SYS_UN_H)) */
 
 static int
 set_unix_port(edge_connection_t *conn, rend_service_port_config_t *p)
@@ -94,7 +94,7 @@ add_unix_port(smartlist_t *ports, rend_service_port_config_t *p)
   return -ENOSYS;
 }
 
-#endif /* HAVE_SYS_UN_H */
+#endif /* defined(HAVE_SYS_UN_H) */
 
 /* Helper function: The key is a digest that we compare to a node_t object
  * current hsdir_index. */
@@ -641,7 +641,7 @@ get_second_cached_disaster_srv(void)
   return cached_disaster_srv[1];
 }
 
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /* When creating a blinded key, we need a parameter which construction is as
  * follow: H(pubkey | [secret] | ed25519-basepoint | nonce).
diff --git a/src/or/hs_common.h b/src/or/hs_common.h
index 5851578fd6..e28ffe1adb 100644
--- a/src/or/hs_common.h
+++ b/src/or/hs_common.h
@@ -266,9 +266,9 @@ STATIC uint64_t get_time_period_length(void);
 STATIC uint8_t *get_first_cached_disaster_srv(void);
 STATIC uint8_t *get_second_cached_disaster_srv(void);
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
-#endif /* HS_COMMON_PRIVATE */
+#endif /* defined(HS_COMMON_PRIVATE) */
 
-#endif /* TOR_HS_COMMON_H */
+#endif /* !defined(TOR_HS_COMMON_H) */
 
diff --git a/src/or/hs_config.h b/src/or/hs_config.h
index 2f8cbdc130..6cd7aed460 100644
--- a/src/or/hs_config.h
+++ b/src/or/hs_config.h
@@ -20,5 +20,5 @@
 
 int hs_config_service_all(const or_options_t *options, int validate_only);
 
-#endif /* TOR_HS_CONFIG_H */
+#endif /* !defined(TOR_HS_CONFIG_H) */
 
diff --git a/src/or/hs_descriptor.h b/src/or/hs_descriptor.h
index 61e7a28c2e..971e856647 100644
--- a/src/or/hs_descriptor.h
+++ b/src/or/hs_descriptor.h
@@ -261,7 +261,7 @@ STATIC size_t decode_superencrypted(const char *message, size_t message_len,
                                    uint8_t **encrypted_out);
 STATIC void desc_plaintext_data_free_contents(hs_desc_plaintext_data_t *desc);
 
-#endif /* HS_DESCRIPTOR_PRIVATE */
+#endif /* defined(HS_DESCRIPTOR_PRIVATE) */
 
-#endif /* TOR_HS_DESCRIPTOR_H */
+#endif /* !defined(TOR_HS_DESCRIPTOR_H) */
 
diff --git a/src/or/hs_ident.h b/src/or/hs_ident.h
index 101c1cfffd..03150d25ea 100644
--- a/src/or/hs_ident.h
+++ b/src/or/hs_ident.h
@@ -137,5 +137,5 @@ void hs_ident_edge_conn_free(hs_ident_edge_conn_t *ident);
 /* Validators */
 int hs_ident_intro_circ_is_valid(const hs_ident_circuit_t *ident);
 
-#endif /* TOR_HS_IDENT_H */
+#endif /* !defined(TOR_HS_IDENT_H) */
 
diff --git a/src/or/hs_intropoint.h b/src/or/hs_intropoint.h
index 5c77f07ec3..749d1530e1 100644
--- a/src/or/hs_intropoint.h
+++ b/src/or/hs_intropoint.h
@@ -73,7 +73,7 @@ STATIC int handle_introduce1(or_circuit_t *client_circ,
 STATIC int validate_introduce1_parsed_cell(const trn_cell_introduce1_t *cell);
 STATIC int circuit_is_suitable_for_introduce1(const or_circuit_t *circ);
 
-#endif /* HS_INTROPOINT_PRIVATE */
+#endif /* defined(HS_INTROPOINT_PRIVATE) */
 
-#endif /* TOR_HS_INTRO_H */
+#endif /* !defined(TOR_HS_INTRO_H) */
 
diff --git a/src/or/hs_ntor.h b/src/or/hs_ntor.h
index d07bff8cf0..77e544a130 100644
--- a/src/or/hs_ntor.h
+++ b/src/or/hs_ntor.h
@@ -63,5 +63,5 @@ int hs_ntor_client_rendezvous2_mac_is_good(
                         const hs_ntor_rend_cell_keys_t *hs_ntor_rend_cell_keys,
                         const uint8_t *rcvd_mac);
 
-#endif
+#endif /* !defined(TOR_HS_NTOR_H) */
 
diff --git a/src/or/hs_service.c b/src/or/hs_service.c
index 05045035f3..d26f49516d 100644
--- a/src/or/hs_service.c
+++ b/src/or/hs_service.c
@@ -910,7 +910,7 @@ write_address_to_file(const hs_service_t *service, const char *fname_)
                       "group-readable.", escaped(fname));
     }
   }
-#endif /* _WIN32 */
+#endif /* !defined(_WIN32) */
 
   /* Success. */
   ret = 0;
@@ -3309,5 +3309,5 @@ get_first_service(void)
   return *obj;
 }
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
diff --git a/src/or/hs_service.h b/src/or/hs_service.h
index 248df27e10..ed1053d850 100644
--- a/src/or/hs_service.h
+++ b/src/or/hs_service.h
@@ -346,9 +346,9 @@ STATIC void service_desc_schedule_upload(hs_service_descriptor_t *desc,
 STATIC int service_desc_hsdirs_changed(const hs_service_t *service,
                                 const hs_service_descriptor_t *desc);
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
-#endif /* HS_SERVICE_PRIVATE */
+#endif /* defined(HS_SERVICE_PRIVATE) */
 
-#endif /* TOR_HS_SERVICE_H */
+#endif /* !defined(TOR_HS_SERVICE_H) */
 
diff --git a/src/or/keypin.h b/src/or/keypin.h
index 2564f5befb..fbb77e5c35 100644
--- a/src/or/keypin.h
+++ b/src/or/keypin.h
@@ -41,7 +41,7 @@ STATIC keypin_ent_t * keypin_parse_journal_line(const char *cp);
 STATIC int keypin_load_journal_impl(const char *data, size_t size);
 
 MOCK_DECL(STATIC void, keypin_add_entry_to_map, (keypin_ent_t *ent));
-#endif
+#endif /* defined(KEYPIN_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_KEYPIN_H) */
 
diff --git a/src/or/main.c b/src/or/main.c
index 117857e543..65b0b8f4df 100644
--- a/src/or/main.c
+++ b/src/or/main.c
@@ -122,9 +122,9 @@
  * Coverity. Here's a kludge to unconfuse it.
  */
 #   define __INCLUDE_LEVEL__ 2
-#   endif
+#endif /* defined(__COVERITY__) && !defined(__INCLUDE_LEVEL__) */
 #include <systemd/sd-daemon.h>
-#endif
+#endif /* defined(HAVE_SYSTEMD) */
 
 void evdns_shutdown(int);
 
@@ -742,7 +742,7 @@ conn_read_callback(evutil_socket_t fd, short event, void *_conn)
                "(fd %d); removing",
                conn_type_to_string(conn->type), (int)conn->s);
       tor_fragile_assert();
-#endif
+#endif /* !defined(_WIN32) */
       if (CONN_IS_EDGE(conn))
         connection_edge_end_errno(TO_EDGE_CONN(conn));
       connection_mark_for_close(conn);
@@ -2227,7 +2227,7 @@ systemd_watchdog_callback(periodic_timer_t *timer, void *arg)
   (void)arg;
   sd_notify(0, "WATCHDOG=1");
 }
-#endif
+#endif /* defined(HAVE_SYSTEMD_209) */
 
 /** Timer: used to invoke refill_callback(). */
 static periodic_timer_t *refill_timer = NULL;
@@ -2291,7 +2291,7 @@ got_libevent_error(void)
   }
   return 0;
 }
-#endif
+#endif /* !defined(_WIN32) */
 
 #define UPTIME_CUTOFF_FOR_NEW_BANDWIDTH_TEST (6*60*60)
 
@@ -2565,7 +2565,7 @@ do_main_loop(void)
       tor_assert(systemd_watchdog_timer);
     }
   }
-#endif
+#endif /* defined(HAVE_SYSTEMD_209) */
 
   if (!refill_timer) {
     struct timeval refill_interval;
@@ -2593,7 +2593,7 @@ do_main_loop(void)
       log_info(LD_GENERAL, "Systemd NOTIFY_SOCKET not present.");
     }
   }
-#endif
+#endif /* defined(HAVE_SYSTEMD) */
 
   return run_main_loop_until_done();
 }
@@ -2646,7 +2646,7 @@ run_main_loop_once(void)
       log_warn(LD_NET, "EINVAL from libevent: should you upgrade libevent?");
       if (got_libevent_error())
         return -1;
-#endif
+#endif /* !defined(_WIN32) */
     } else {
       tor_assert_nonfatal_once(! ERRNO_IS_EINPROGRESS(e));
       log_debug(LD_NET,"libevent call interrupted.");
@@ -3002,7 +3002,7 @@ handle_signals(int is_parent)
 #ifdef SIGXFSZ
     sigaction(SIGXFSZ, &action, NULL);
 #endif
-#endif
+#endif /* !defined(_WIN32) */
   }
 }
 
@@ -3730,7 +3730,7 @@ tor_main(int argc, char *argv[])
       setdeppolicy(3);
     }
   }
-#endif
+#endif /* defined(_WIN32) */
 
   configure_backtrace_handler(get_version());
 
@@ -3746,14 +3746,14 @@ tor_main(int argc, char *argv[])
     int r = crypto_use_tor_alloc_functions();
     tor_assert(r == 0);
   }
-#endif
+#endif /* defined(USE_DMALLOC) */
 #ifdef NT_SERVICE
   {
      int done = 0;
      result = nt_service_parse_options(argc, argv, &done);
      if (done) return result;
   }
-#endif
+#endif /* defined(NT_SERVICE) */
   if (tor_init(argc, argv)<0)
     return -1;
 
diff --git a/src/or/main.h b/src/or/main.h
index 57aa372750..132ab12bbb 100644
--- a/src/or/main.h
+++ b/src/or/main.h
@@ -95,7 +95,7 @@ STATIC void teardown_periodic_events(void);
 #ifdef TOR_UNIT_TESTS
 extern smartlist_t *connection_array;
 #endif
-#endif
+#endif /* defined(MAIN_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_MAIN_H) */
 
diff --git a/src/or/microdesc.h b/src/or/microdesc.h
index 943873066e..b40d66b3e3 100644
--- a/src/or/microdesc.h
+++ b/src/or/microdesc.h
@@ -50,5 +50,5 @@ int we_fetch_microdescriptors(const or_options_t *options);
 int we_fetch_router_descriptors(const or_options_t *options);
 int we_use_microdescriptors_for_circuits(const or_options_t *options);
 
-#endif
+#endif /* !defined(TOR_MICRODESC_H) */
 
diff --git a/src/or/networkstatus.c b/src/or/networkstatus.c
index 00d9222ef1..93bb8643d8 100644
--- a/src/or/networkstatus.c
+++ b/src/or/networkstatus.c
@@ -1628,7 +1628,7 @@ networkstatus_set_current_consensus_from_ns(networkstatus_t *c,
   }
   return current_md_consensus ? 0 : -1;
 }
-#endif //TOR_UNIT_TESTS
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /**
  * Return true if any option is set in <b>options</b> to make us behave
diff --git a/src/or/networkstatus.h b/src/or/networkstatus.h
index 89ff7eaba6..39a0f753d8 100644
--- a/src/or/networkstatus.h
+++ b/src/or/networkstatus.h
@@ -137,8 +137,8 @@ STATIC int networkstatus_set_current_consensus_from_ns(networkstatus_t *c,
                                                 const char *flavor);
 extern networkstatus_t *current_ns_consensus;
 extern networkstatus_t *current_md_consensus;
-#endif
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
+#endif /* defined(NETWORKSTATUS_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_NETWORKSTATUS_H) */
 
diff --git a/src/or/nodelist.h b/src/or/nodelist.h
index 427e449ad9..754990ac8d 100644
--- a/src/or/nodelist.h
+++ b/src/or/nodelist.h
@@ -149,9 +149,9 @@ int count_loading_descriptors_progress(void);
 STATIC void
 node_set_hsdir_index(node_t *node, const networkstatus_t *ns);
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
-#endif /* NODELIST_PRIVATE */
+#endif /* defined(NODELIST_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_NODELIST_H) */
 
diff --git a/src/or/ntmain.c b/src/or/ntmain.c
index 7a85ba9708..508e5844eb 100644
--- a/src/or/ntmain.c
+++ b/src/or/ntmain.c
@@ -502,7 +502,7 @@ nt_service_command_line(int *using_default_torrc)
   tor_exe_ascii[sizeof(tor_exe_ascii)-1] = '\0';
 #else
   strlcpy(tor_exe_ascii, tor_exe, sizeof(tor_exe_ascii));
-#endif
+#endif /* defined(UNICODE) */
 
   /* Allocate a string for the NT service command line and */
   /* Format the service command */
@@ -778,5 +778,5 @@ nt_service_parse_options(int argc, char **argv, int *should_exit)
   return 0;
 }
 
-#endif
+#endif /* defined(_WIN32) */
 
diff --git a/src/or/ntmain.h b/src/or/ntmain.h
index 4b771b1828..81b7159855 100644
--- a/src/or/ntmain.h
+++ b/src/or/ntmain.h
@@ -22,7 +22,7 @@ int nt_service_is_stopping(void);
 void nt_service_set_state(DWORD state);
 #else
 #define nt_service_is_stopping() 0
-#endif
+#endif /* defined(NT_SERVICE) */
 
-#endif
+#endif /* !defined(TOR_NTMAIN_H) */
 
diff --git a/src/or/onion.h b/src/or/onion.h
index 37a7b08cb6..95544dfac1 100644
--- a/src/or/onion.h
+++ b/src/or/onion.h
@@ -119,5 +119,5 @@ int extend_cell_format(uint8_t *command_out, uint16_t *len_out,
 int extended_cell_format(uint8_t *command_out, uint16_t *len_out,
                          uint8_t *payload_out, const extended_cell_t *cell_in);
 
-#endif
+#endif /* !defined(TOR_ONION_H) */
 
diff --git a/src/or/onion_fast.h b/src/or/onion_fast.h
index b31f8e9492..3a5aefea3f 100644
--- a/src/or/onion_fast.h
+++ b/src/or/onion_fast.h
@@ -35,5 +35,5 @@ int fast_client_handshake(const fast_handshake_state_t *handshake_state,
                           size_t key_out_len,
                           const char **msg_out);
 
-#endif
+#endif /* !defined(TOR_ONION_FAST_H) */
 
diff --git a/src/or/onion_ntor.h b/src/or/onion_ntor.h
index 158c499de4..02dea2dfc1 100644
--- a/src/or/onion_ntor.h
+++ b/src/or/onion_ntor.h
@@ -55,7 +55,7 @@ struct ntor_handshake_state_t {
   curve25519_public_key_t pubkey_X;
   /** @} */
 };
-#endif
+#endif /* defined(ONION_NTOR_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_ONION_NTOR_H) */
 
diff --git a/src/or/onion_tap.h b/src/or/onion_tap.h
index bd625231f4..713c1d7391 100644
--- a/src/or/onion_tap.h
+++ b/src/or/onion_tap.h
@@ -34,5 +34,5 @@ int onion_skin_TAP_client_handshake(crypto_dh_t *handshake_state,
                                 size_t key_out_len,
                                 const char **msg_out);
 
-#endif
+#endif /* !defined(TOR_ONION_TAP_H) */
 
diff --git a/src/or/or.h b/src/or/or.h
index 53ba94e90e..4fc0e788a0 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -64,7 +64,7 @@
 #include <process.h>
 #include <direct.h>
 #include <windows.h>
-#endif
+#endif /* defined(_WIN32) */
 
 #include "crypto.h"
 #include "crypto_format.h"
@@ -1834,7 +1834,7 @@ typedef struct dir_connection_t {
 
   /** Number of RELAY_DATA cells sent. */
   uint32_t data_cells_sent;
-#endif
+#endif /* defined(MEASUREMENTS_21206) */
 } dir_connection_t;
 
 /** Subtype of connection_t for an connection to a controller. */
@@ -5051,7 +5051,7 @@ typedef struct measured_bw_line_t {
   long int bw_kb;
 } measured_bw_line_t;
 
-#endif
+#endif /* defined(DIRSERV_PRIVATE) */
 
 /********************************* dirvote.c ************************/
 
@@ -5464,5 +5464,5 @@ typedef struct tor_version_t {
   char git_tag[DIGEST_LEN];
 } tor_version_t;
 
-#endif
+#endif /* !defined(TOR_OR_H) */
 
diff --git a/src/or/parsecommon.h b/src/or/parsecommon.h
index 5e5f9f4db6..903d94478b 100644
--- a/src/or/parsecommon.h
+++ b/src/or/parsecommon.h
@@ -318,5 +318,5 @@ directory_token_t *find_opt_by_keyword(smartlist_t *s,
                                        directory_keyword keyword);
 smartlist_t * find_all_by_keyword(const smartlist_t *s, directory_keyword k);
 
-#endif /* TOR_PARSECOMMON_H */
+#endif /* !defined(TOR_PARSECOMMON_H) */
 
diff --git a/src/or/periodic.h b/src/or/periodic.h
index 88d00cc7e9..8baf3994eb 100644
--- a/src/or/periodic.h
+++ b/src/or/periodic.h
@@ -33,5 +33,5 @@ void periodic_event_setup(periodic_event_item_t *event);
 void periodic_event_destroy(periodic_event_item_t *event);
 void periodic_event_reschedule(periodic_event_item_t *event);
 
-#endif
+#endif /* !defined(TOR_PERIODIC_H) */
 
diff --git a/src/or/policies.h b/src/or/policies.h
index ce08d497e9..52ff4e2f99 100644
--- a/src/or/policies.h
+++ b/src/or/policies.h
@@ -141,7 +141,7 @@ STATIC const tor_addr_port_t * fascist_firewall_choose_address(
                                           firewall_connection_t fw_connection,
                                           int pref_only, int pref_ipv6);
 
-#endif
+#endif /* defined(POLICIES_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_POLICIES_H) */
 
diff --git a/src/or/proto_cell.h b/src/or/proto_cell.h
index 91729a391e..bbc14b9a02 100644
--- a/src/or/proto_cell.h
+++ b/src/or/proto_cell.h
@@ -13,5 +13,5 @@ struct var_cell_t;
 int fetch_var_cell_from_buf(struct buf_t *buf, struct var_cell_t **out,
                             int linkproto);
 
-#endif
+#endif /* !defined(TOR_PROTO_CELL_H) */
 
diff --git a/src/or/proto_control0.h b/src/or/proto_control0.h
index 6df6bebaa5..0cc8eacad0 100644
--- a/src/or/proto_control0.h
+++ b/src/or/proto_control0.h
@@ -10,5 +10,5 @@
 struct buf_t;
 int peek_buf_has_control0_command(struct buf_t *buf);
 
-#endif
+#endif /* !defined(TOR_PROTO_CONTROL0_H) */
 
diff --git a/src/or/proto_ext_or.h b/src/or/proto_ext_or.h
index 2ef185356c..cc504d18e3 100644
--- a/src/or/proto_ext_or.h
+++ b/src/or/proto_ext_or.h
@@ -13,5 +13,5 @@ struct ext_or_cmt_t;
 int fetch_ext_or_command_from_buf(struct buf_t *buf,
                                   struct ext_or_cmd_t **out);
 
-#endif
+#endif /* !defined(TOR_PROTO_EXT_OR_H) */
 
diff --git a/src/or/proto_http.h b/src/or/proto_http.h
index dbff823cce..805686070f 100644
--- a/src/or/proto_http.h
+++ b/src/or/proto_http.h
@@ -20,5 +20,5 @@ STATIC int buf_http_find_content_length(const char *headers, size_t headerlen,
                                         size_t *result_out);
 #endif
 
-#endif
+#endif /* !defined(TOR_PROTO_HTTP_H) */
 
diff --git a/src/or/proto_socks.h b/src/or/proto_socks.h
index 4a24773199..a714151414 100644
--- a/src/or/proto_socks.h
+++ b/src/or/proto_socks.h
@@ -16,5 +16,5 @@ int fetch_from_buf_socks(struct buf_t *buf, socks_request_t *req,
                          int log_sockstype, int safe_socks);
 int fetch_from_buf_socks_client(buf_t *buf, int state, char **reason);
 
-#endif
+#endif /* !defined(TOR_PROTO_SOCKS_H) */
 
diff --git a/src/or/protover.h b/src/or/protover.h
index ec8da1a0d0..657977279e 100644
--- a/src/or/protover.h
+++ b/src/or/protover.h
@@ -75,7 +75,7 @@ STATIC void proto_entry_free(proto_entry_t *entry);
 STATIC char *encode_protocol_list(const smartlist_t *sl);
 STATIC const char *protocol_type_to_str(protocol_type_t pr);
 STATIC int str_to_protocol_type(const char *s, protocol_type_t *pr_out);
-#endif
+#endif /* defined(PROTOVER_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_PROTOVER_H) */
 
diff --git a/src/or/reasons.c b/src/or/reasons.c
index 717cf57c24..03d49418da 100644
--- a/src/or/reasons.c
+++ b/src/or/reasons.c
@@ -167,7 +167,7 @@ stream_end_reason_to_socks5_response(int reason)
 #else
 #define E_CASE(s) case s
 #define S_CASE(s) case s
-#endif
+#endif /* defined(_WIN32) */
 
 /** Given an errno from a failed exit connection, return a reason code
  * appropriate for use in a RELAY END cell. */
diff --git a/src/or/reasons.h b/src/or/reasons.h
index f98db55bdd..3d6ba8fc83 100644
--- a/src/or/reasons.h
+++ b/src/or/reasons.h
@@ -28,5 +28,5 @@ const char *socks5_response_code_to_string(uint8_t code);
 const char *bandwidth_weight_rule_to_string(enum bandwidth_weight_rule_t rule);
 const char *end_reason_to_http_connect_response_line(int endreason);
 
-#endif
+#endif /* !defined(TOR_REASONS_H) */
 
diff --git a/src/or/relay.c b/src/or/relay.c
index c00afc8e72..2bfec342d3 100644
--- a/src/or/relay.c
+++ b/src/or/relay.c
@@ -818,7 +818,7 @@ connection_edge_send_command(edge_connection_t *fromconn,
   if (linked_conn && linked_conn->type == CONN_TYPE_DIR) {
     ++(TO_DIR_CONN(linked_conn)->data_cells_sent);
   }
-#endif
+#endif /* defined(MEASUREMENTS_21206) */
 
   return relay_send_command_from_edge(fromconn->stream_id, circ,
                                       relay_command, payload,
@@ -1685,7 +1685,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
       if (linked_conn && linked_conn->type == CONN_TYPE_DIR) {
         ++(TO_DIR_CONN(linked_conn)->data_cells_received);
       }
-#endif
+#endif /* defined(MEASUREMENTS_21206) */
 
       if (!optimistic_data) {
         /* Only send a SENDME if we're not getting optimistic data; otherwise
@@ -2383,7 +2383,7 @@ circuit_consider_sending_sendme(circuit_t *circ, crypt_path_t *layer_hint)
      assert_circuit_mux_okay(chan)
 #else
 #define assert_cmux_ok_paranoid(chan)
-#endif
+#endif /* defined(ACTIVE_CIRCUITS_PARANOIA) */
 
 /** The total number of cells we have allocated. */
 static size_t total_cells_allocated = 0;
@@ -2851,7 +2851,7 @@ get_max_middle_cells(void)
 {
   return ORCIRC_MAX_MIDDLE_CELLS;
 }
-#endif
+#endif /* 0 */
 
 /** Add <b>cell</b> to the queue of <b>circ</b> writing to <b>chan</b>
  * transmitting in <b>direction</b>. */
@@ -2961,7 +2961,7 @@ append_cell_to_circuit_queue(circuit_t *circ, channel_t *chan,
       }
     }
   }
-#endif
+#endif /* 0 */
 
   cell_queue_append_packed_copy(circ, queue, exitward, cell,
                                 chan->wide_circ_ids, 1);
diff --git a/src/or/relay.h b/src/or/relay.h
index a160cd5551..2412dcb23c 100644
--- a/src/or/relay.h
+++ b/src/or/relay.h
@@ -104,7 +104,7 @@ STATIC packed_cell_t *packed_cell_new(void);
 STATIC packed_cell_t *cell_queue_pop(cell_queue_t *queue);
 STATIC size_t cell_queues_get_total_allocation(void);
 STATIC int cell_queues_check_size(void);
-#endif
+#endif /* defined(RELAY_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_RELAY_H) */
 
diff --git a/src/or/rendcache.h b/src/or/rendcache.h
index 1bd3be2243..5b13eadfa1 100644
--- a/src/or/rendcache.h
+++ b/src/or/rendcache.h
@@ -115,8 +115,8 @@ extern strmap_t *rend_cache;
 extern strmap_t *rend_cache_failure;
 extern digestmap_t *rend_cache_v2_dir;
 extern size_t rend_cache_total_allocation;
-#endif
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
+#endif /* defined(RENDCACHE_PRIVATE) */
 
-#endif /* TOR_RENDCACHE_H */
+#endif /* !defined(TOR_RENDCACHE_H) */
 
diff --git a/src/or/rendclient.c b/src/or/rendclient.c
index 55f79c50fb..3274819241 100644
--- a/src/or/rendclient.c
+++ b/src/or/rendclient.c
@@ -440,7 +440,7 @@ directory_get_from_hs_dir(const char *desc_id,
   const int how_to_fetch = tor2web_mode ? DIRIND_ONEHOP : DIRIND_ANONYMOUS;
 #else
   const int how_to_fetch = DIRIND_ANONYMOUS;
-#endif
+#endif /* defined(ENABLE_TOR2WEB_MODE) */
 
   tor_assert(desc_id);
   tor_assert(rend_query);
@@ -1218,7 +1218,7 @@ rend_client_allow_non_anonymous_connection(const or_options_t *options)
 #else
   (void)options;
   return 0;
-#endif
+#endif /* defined(NON_ANONYMOUS_MODE_ENABLED) */
 }
 
 /* At compile-time, was non-anonymous mode enabled via
@@ -1233,6 +1233,6 @@ rend_client_non_anonymous_mode_enabled(const or_options_t *options)
   return 1;
 #else
   return 0;
-#endif
+#endif /* defined(NON_ANONYMOUS_MODE_ENABLED) */
 }
 
diff --git a/src/or/rendclient.h b/src/or/rendclient.h
index ac0503bade..e8495ce09c 100644
--- a/src/or/rendclient.h
+++ b/src/or/rendclient.h
@@ -50,5 +50,5 @@ void rend_service_authorization_free_all(void);
 int rend_client_allow_non_anonymous_connection(const or_options_t *options);
 int rend_client_non_anonymous_mode_enabled(const or_options_t *options);
 
-#endif
+#endif /* !defined(TOR_RENDCLIENT_H) */
 
diff --git a/src/or/rendcommon.h b/src/or/rendcommon.h
index af8dd60099..c35d7272fd 100644
--- a/src/or/rendcommon.h
+++ b/src/or/rendcommon.h
@@ -68,7 +68,7 @@ void assert_circ_anonymity_ok(const origin_circuit_t *circ,
 STATIC int
 rend_desc_v2_is_parsable(rend_encoded_v2_service_descriptor_t *desc);
 
-#endif
+#endif /* defined(RENDCOMMON_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_RENDCOMMON_H) */
 
diff --git a/src/or/rendmid.h b/src/or/rendmid.h
index daf9e2885e..6cc1fc8d95 100644
--- a/src/or/rendmid.h
+++ b/src/or/rendmid.h
@@ -21,5 +21,5 @@ int rend_mid_establish_rendezvous(or_circuit_t *circ, const uint8_t *request,
 int rend_mid_rendezvous(or_circuit_t *circ, const uint8_t *request,
                         size_t request_len);
 
-#endif
+#endif /* !defined(TOR_RENDMID_H) */
 
diff --git a/src/or/rendservice.c b/src/or/rendservice.c
index 01147c0072..7127ed1ccd 100644
--- a/src/or/rendservice.c
+++ b/src/or/rendservice.c
@@ -1459,7 +1459,7 @@ rend_service_load_keys(rend_service_t *s)
       log_warn(LD_FS,"Unable to make hidden hostname file %s group-readable.",
                fname);
   }
-#endif
+#endif /* !defined(_WIN32) */
 
   /* If client authorization is configured, load or generate keys. */
   if (s->auth_type != REND_NO_AUTH) {
@@ -4370,5 +4370,5 @@ set_rend_rend_service_staging_list(smartlist_t *new_list)
   rend_service_staging_list = new_list;
 }
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
diff --git a/src/or/rendservice.h b/src/or/rendservice.h
index ed1044f04a..5946e31861 100644
--- a/src/or/rendservice.h
+++ b/src/or/rendservice.h
@@ -131,9 +131,9 @@ STATIC void set_rend_service_list(smartlist_t *new_list);
 STATIC void set_rend_rend_service_staging_list(smartlist_t *new_list);
 STATIC void rend_service_prune_list_impl_(void);
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
-#endif /* RENDSERVICE_PRIVATE */
+#endif /* defined(RENDSERVICE_PRIVATE) */
 
 int rend_num_services(void);
 int rend_config_service(const config_line_t *line_,
@@ -214,5 +214,5 @@ int rend_service_allow_non_anonymous_connection(const or_options_t *options);
 int rend_service_reveal_startup_time(const or_options_t *options);
 int rend_service_non_anonymous_mode_enabled(const or_options_t *options);
 
-#endif
+#endif /* !defined(TOR_RENDSERVICE_H) */
 
diff --git a/src/or/rephist.h b/src/or/rephist.h
index 8f6d46616d..496e366865 100644
--- a/src/or/rephist.h
+++ b/src/or/rephist.h
@@ -143,5 +143,5 @@ void rep_hist_reset_padding_counts(void);
 void rep_hist_prep_published_padding_counts(time_t now);
 void rep_hist_padding_count_timers(uint64_t num_timers);
 
-#endif
+#endif /* !defined(TOR_REPHIST_H) */
 
diff --git a/src/or/replaycache.h b/src/or/replaycache.h
index 0d637939a4..1cae3497ae 100644
--- a/src/or/replaycache.h
+++ b/src/or/replaycache.h
@@ -29,7 +29,7 @@ struct replaycache_s {
   digest256map_t *digests_seen;
 };
 
-#endif /* REPLAYCACHE_PRIVATE */
+#endif /* defined(REPLAYCACHE_PRIVATE) */
 
 /* replaycache_t free/new */
 
@@ -51,7 +51,7 @@ STATIC int replaycache_add_and_test_internal(
 STATIC void replaycache_scrub_if_needed_internal(
     time_t present, replaycache_t *r);
 
-#endif /* REPLAYCACHE_PRIVATE */
+#endif /* defined(REPLAYCACHE_PRIVATE) */
 
 /*
  * replaycache_t methods
@@ -62,5 +62,5 @@ int replaycache_add_test_and_elapsed(
     replaycache_t *r, const void *data, size_t len, time_t *elapsed);
 void replaycache_scrub_if_needed(replaycache_t *r);
 
-#endif
+#endif /* !defined(TOR_REPLAYCACHE_H) */
 
diff --git a/src/or/router.c b/src/or/router.c
index d2d3d12f5b..172531e70e 100644
--- a/src/or/router.c
+++ b/src/or/router.c
@@ -1945,7 +1945,7 @@ router_compare_to_my_exit_policy(const tor_addr_t *addr, uint16_t port)
       desc_routerinfo->ipv6_exit_policy &&
       compare_tor_addr_to_short_policy(addr, port,
                                me->ipv6_exit_policy) != ADDR_POLICY_ACCEPTED;
-#endif
+#endif /* 0 */
   } else {
     return -1;
   }
@@ -3047,7 +3047,7 @@ router_dump_router_to_string(routerinfo_t *router,
     tor_free(s_dup);
     routerinfo_free(ri_tmp);
   }
-#endif
+#endif /* defined(DEBUG_ROUTER_DUMP_ROUTER_TO_STRING) */
 
   goto done;
 
diff --git a/src/or/router.h b/src/or/router.h
index 97f331713a..3351400911 100644
--- a/src/or/router.h
+++ b/src/or/router.h
@@ -160,5 +160,5 @@ STATIC void get_platform_str(char *platform, size_t len);
 STATIC int router_write_fingerprint(int hashed);
 #endif
 
-#endif
+#endif /* !defined(TOR_ROUTER_H) */
 
diff --git a/src/or/routerkeys.c b/src/or/routerkeys.c
index 4822ff3be3..7295c19653 100644
--- a/src/or/routerkeys.c
+++ b/src/or/routerkeys.c
@@ -1134,7 +1134,7 @@ init_mock_ed_keys(const crypto_pk_t *rsa_identity_key)
 }
 #undef MAKEKEY
 #undef MAKECERT
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /**
  * Print the ISO8601-formated <b>expiration</b> for a certificate with
@@ -1262,7 +1262,7 @@ get_master_identity_keypair(void)
 {
   return master_identity_key;
 }
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
 const ed25519_keypair_t *
 get_master_signing_keypair(void)
diff --git a/src/or/routerkeys.h b/src/or/routerkeys.h
index 0cf13e7600..3e67952ea0 100644
--- a/src/or/routerkeys.h
+++ b/src/or/routerkeys.h
@@ -81,5 +81,5 @@ const ed25519_keypair_t *get_master_identity_keypair(void);
 void init_mock_ed_keys(const crypto_pk_t *rsa_identity_key);
 #endif
 
-#endif
+#endif /* !defined(TOR_ROUTERKEYS_H) */
 
diff --git a/src/or/routerlist.c b/src/or/routerlist.c
index 9111d93c3c..9b056e80aa 100644
--- a/src/or/routerlist.c
+++ b/src/or/routerlist.c
@@ -1872,7 +1872,7 @@ router_picked_poor_directory_log(const routerstatus_t *rs)
       || !router_have_minimum_dir_info()) {
     return;
   }
-#endif
+#endif /* !LOG_FALSE_POSITIVES_DURING_BOOTSTRAP */
 
   /* We couldn't find a node, or the one we have doesn't fit our preferences.
    * Sometimes this is normal, sometimes it can be a reachability issue. */
@@ -4052,7 +4052,7 @@ routerlist_remove_old_cached_routers_with_id(time_t now,
     signed_descriptor_t *r = smartlist_get(lst, i);
     tor_assert(tor_memeq(ident, r->identity_digest, DIGEST_LEN));
   }
-#endif
+#endif /* 1 */
   /* Check whether we need to do anything at all. */
   {
     int mdpr = directory_caches_dir_info(get_options()) ? 2 : 1;
diff --git a/src/or/routerlist.h b/src/or/routerlist.h
index 27c8d88f05..8384c7eb8c 100644
--- a/src/or/routerlist.h
+++ b/src/or/routerlist.h
@@ -251,7 +251,7 @@ MOCK_DECL(STATIC void, initiate_descriptor_downloads,
 STATIC int router_is_already_dir_fetching(const tor_addr_port_t *ap,
                                           int serverdesc, int microdesc);
 
-#endif
+#endif /* defined(ROUTERLIST_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_ROUTERLIST_H) */
 
diff --git a/src/or/routerparse.c b/src/or/routerparse.c
index 08c3fc0a02..4541781beb 100644
--- a/src/or/routerparse.c
+++ b/src/or/routerparse.c
@@ -388,9 +388,9 @@ static int check_signature_token(const char *digest,
   log_debug(LD_MM, "Area for %s has %lu allocated; using %lu.",   \
             name, (unsigned long)alloc, (unsigned long)used);     \
   STMT_END
-#else
+#else /* !(defined(DEBUG_AREA_ALLOC)) */
 #define DUMP_AREA(a,name) STMT_NIL
-#endif
+#endif /* defined(DEBUG_AREA_ALLOC) */
 
 /* Dump mechanism for unparseable descriptors */
 
@@ -701,7 +701,7 @@ dump_desc_populate_one_file, (const char *dirname, const char *f))
     goto done;
     /* LCOV_EXCL_STOP */
   }
-#endif
+#endif /* SIZE_MAX > UINT64_MAX */
   if (BUG(st.st_size < 0)) {
     /* LCOV_EXCL_START
      * Should be impossible, since the OS isn't supposed to be b0rken. */
@@ -1425,9 +1425,9 @@ dump_distinct_digest_count(int severity)
     verified_digests = digestmap_new();
   tor_log(severity, LD_GENERAL, "%d *distinct* router digests verified",
       digestmap_size(verified_digests));
-#else
+#else /* !(defined(COUNT_DISTINCT_DIGESTS)) */
   (void)severity; /* suppress "unused parameter" warning */
-#endif
+#endif /* defined(COUNT_DISTINCT_DIGESTS) */
 }
 
 /** Try to find an IPv6 OR port in <b>list</b> of directory_token_t's
diff --git a/src/or/routerparse.h b/src/or/routerparse.h
index 088f773c5e..c4c8635f4b 100644
--- a/src/or/routerparse.h
+++ b/src/or/routerparse.h
@@ -133,9 +133,9 @@ MOCK_DECL(STATIC int, router_compute_hash_final,(char *digest,
                            digest_algorithm_t alg));
 MOCK_DECL(STATIC int, signed_digest_equals,
           (const uint8_t *d1, const uint8_t *d2, size_t len));
-#endif
+#endif /* defined(ROUTERPARSE_PRIVATE) */
 
 #define ED_DESC_SIGNATURE_PREFIX "Tor router descriptor signature v1"
 
-#endif
+#endif /* !defined(TOR_ROUTERPARSE_H) */
 
diff --git a/src/or/routerset.h b/src/or/routerset.h
index a63677b471..d8819ef3fd 100644
--- a/src/or/routerset.h
+++ b/src/or/routerset.h
@@ -82,6 +82,6 @@ struct routerset_t {
    * reloaded. */
   bitarray_t *countries;
 };
-#endif
-#endif
+#endif /* defined(ROUTERSET_PRIVATE) */
+#endif /* !defined(TOR_ROUTERSET_H) */
 
diff --git a/src/or/scheduler.c b/src/or/scheduler.c
index 4a9f3dcaf6..2d6f7fc4bd 100644
--- a/src/or/scheduler.c
+++ b/src/or/scheduler.c
@@ -275,7 +275,7 @@ select_scheduler(void)
     the_scheduler = get_vanilla_scheduler();
     return;
   }
-#endif
+#endif /* defined(TOR_UNIT_TESTS) */
 
   /* This list is ordered that is first entry has the first priority. Thus, as
    * soon as we find a scheduler type that we can use, we use it and stop. */
@@ -295,9 +295,9 @@ select_scheduler(void)
           log_notice(LD_SCHED, "Scheduler type KIST has been disabled by "
                                "the consensus.");
         }
-#else /* HAVE_KIST_SUPPORT */
+#else /* !(defined(HAVE_KIST_SUPPORT)) */
         log_info(LD_SCHED, "Scheduler type KIST not built in");
-#endif /* HAVE_KIST_SUPPORT */
+#endif /* defined(HAVE_KIST_SUPPORT) */
         continue;
       }
       the_scheduler = get_kist_scheduler();
@@ -647,5 +647,5 @@ scheduler_touch_channel(channel_t *chan)
   /* else no-op, since it isn't in the queue */
 }
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
diff --git a/src/or/scheduler.h b/src/or/scheduler.h
index 98c3599817..3c0748fa68 100644
--- a/src/or/scheduler.h
+++ b/src/or/scheduler.h
@@ -149,7 +149,7 @@ extern smartlist_t *channels_pending;
 extern struct event *run_sched_ev;
 extern const scheduler_t *the_scheduler;
 void scheduler_touch_channel(channel_t *chan);
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
 /*********************************
  * Defined in scheduler_kist.c
@@ -190,7 +190,7 @@ int32_t kist_scheduler_run_interval(const networkstatus_t *ns);
 extern int32_t sched_run_interval;
 #endif /* TOR_UNIT_TESTS */
 
-#endif /* SCHEDULER_KIST_PRIVATE */
+#endif /* defined(SCHEDULER_KIST_PRIVATE) */
 
 /*********************************
  * Defined in scheduler_vanilla.c
@@ -198,7 +198,7 @@ extern int32_t sched_run_interval;
 
 scheduler_t *get_vanilla_scheduler(void);
 
-#endif /* SCHEDULER_PRIVATE_ */
+#endif /* defined(SCHEDULER_PRIVATE_) */
 
-#endif /* TOR_SCHEDULER_H */
+#endif /* !defined(TOR_SCHEDULER_H) */
 
diff --git a/src/or/scheduler_kist.c b/src/or/scheduler_kist.c
index 8595a340ef..2249d49f79 100644
--- a/src/or/scheduler_kist.c
+++ b/src/or/scheduler_kist.c
@@ -36,10 +36,10 @@ static unsigned int kist_lite_mode = 0;
  * changed and it doesn't recognized the values passed to the syscalls needed
  * by KIST. In that case, fallback to the naive approach. */
 static unsigned int kist_no_kernel_support = 0;
-#else
+#else /* !(defined(HAVE_KIST_SUPPORT)) */
 static unsigned int kist_no_kernel_support = 1;
 static unsigned int kist_lite_mode = 1;
-#endif
+#endif /* defined(HAVE_KIST_SUPPORT) */
 
 /* Socket_table hash table stuff. The socket_table keeps track of per-socket
  * limit information imposed by kist and used by kist. */
@@ -289,9 +289,9 @@ update_socket_info_impl, (socket_table_ent_t *ent))
   ent->limit = (uint64_t)tcp_space + (uint64_t)extra_space;
   return;
 
-#else /* HAVE_KIST_SUPPORT */
+#else /* !(defined(HAVE_KIST_SUPPORT)) */
   goto fallback;
-#endif /* HAVE_KIST_SUPPORT */
+#endif /* defined(HAVE_KIST_SUPPORT) */
 
  fallback:
   /* If all of a sudden we don't have kist support, we just zero out all the
@@ -764,7 +764,7 @@ scheduler_can_use_kist(void)
   return run_interval > 0;
 }
 
-#else /* HAVE_KIST_SUPPORT */
+#else /* !(defined(HAVE_KIST_SUPPORT)) */
 
 int
 scheduler_can_use_kist(void)
@@ -772,5 +772,5 @@ scheduler_can_use_kist(void)
   return 0;
 }
 
-#endif /* HAVE_KIST_SUPPORT */
+#endif /* defined(HAVE_KIST_SUPPORT) */
 
diff --git a/src/or/shared_random.c b/src/or/shared_random.c
index e4ee64139a..bbb7af0a33 100644
--- a/src/or/shared_random.c
+++ b/src/or/shared_random.c
@@ -1447,5 +1447,5 @@ set_num_srv_agreements(int32_t value)
   num_srv_agreements_from_vote = value;
 }
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
diff --git a/src/or/shared_random.h b/src/or/shared_random.h
index 76d5b95422..c0992489cb 100644
--- a/src/or/shared_random.h
+++ b/src/or/shared_random.h
@@ -160,7 +160,7 @@ STATIC int should_keep_commit(const sr_commit_t *commit,
                               sr_phase_t phase);
 STATIC void save_commit_during_reveal_phase(const sr_commit_t *commit);
 
-#endif /* SHARED_RANDOM_PRIVATE */
+#endif /* defined(SHARED_RANDOM_PRIVATE) */
 
 #ifdef TOR_UNIT_TESTS
 
@@ -168,5 +168,5 @@ void set_num_srv_agreements(int32_t value);
 
 #endif /* TOR_UNIT_TESTS */
 
-#endif /* TOR_SHARED_RANDOM_H */
+#endif /* !defined(TOR_SHARED_RANDOM_H) */
 
diff --git a/src/or/shared_random_state.c b/src/or/shared_random_state.c
index 5fcf88cc4a..13ef95bb0c 100644
--- a/src/or/shared_random_state.c
+++ b/src/or/shared_random_state.c
@@ -1391,5 +1391,5 @@ get_sr_state(void)
   return sr_state;
 }
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
diff --git a/src/or/shared_random_state.h b/src/or/shared_random_state.h
index 837fa75392..a154eb5636 100644
--- a/src/or/shared_random_state.h
+++ b/src/or/shared_random_state.h
@@ -139,14 +139,14 @@ STATIC void new_protocol_run(time_t valid_after);
 STATIC void state_rotate_srv(void);
 STATIC int is_phase_transition(sr_phase_t next_phase);
 
-#endif /* SHARED_RANDOM_STATE_PRIVATE */
+#endif /* defined(SHARED_RANDOM_STATE_PRIVATE) */
 
 #ifdef TOR_UNIT_TESTS
 
 STATIC void set_sr_phase(sr_phase_t phase);
 STATIC sr_state_t *get_sr_state(void);
 
-#endif /* TOR_UNIT_TESTS */
+#endif /* defined(TOR_UNIT_TESTS) */
 
-#endif /* TOR_SHARED_RANDOM_STATE_H */
+#endif /* !defined(TOR_SHARED_RANDOM_STATE_H) */
 
diff --git a/src/or/statefile.h b/src/or/statefile.h
index 10c09324bc..574afb3622 100644
--- a/src/or/statefile.h
+++ b/src/or/statefile.h
@@ -24,5 +24,5 @@ STATIC void or_state_free(or_state_t *state);
 STATIC or_state_t *or_state_new(void);
 #endif
 
-#endif
+#endif /* !defined(TOR_STATEFILE_H) */
 
diff --git a/src/or/status.h b/src/or/status.h
index c1a0033ce0..49da6abc0f 100644
--- a/src/or/status.h
+++ b/src/or/status.h
@@ -14,5 +14,5 @@ STATIC char *secs_to_uptime(long secs);
 STATIC char *bytes_to_usage(uint64_t bytes);
 #endif
 
-#endif
+#endif /* !defined(TOR_STATUS_H) */
 
diff --git a/src/or/torcert.h b/src/or/torcert.h
index 416ff7aa23..c77ae2089d 100644
--- a/src/or/torcert.h
+++ b/src/or/torcert.h
@@ -101,5 +101,5 @@ void or_handshake_certs_check_both(int severity,
 
 int tor_cert_encode_ed22519(const tor_cert_t *cert, char **cert_str_out);
 
-#endif
+#endif /* !defined(TORCERT_H_INCLUDED) */
 
diff --git a/src/or/transports.c b/src/or/transports.c
index 31849a8d15..68d1354844 100644
--- a/src/or/transports.c
+++ b/src/or/transports.c
@@ -527,12 +527,12 @@ launch_managed_proxy(managed_proxy_t *mp)
                                 (const char **)mp->argv,
                                 env,
                                 &mp->process_handle);
-#else
+#else /* !(defined(_WIN32)) */
   retval = tor_spawn_background(mp->argv[0],
                                 (const char **)mp->argv,
                                 env,
                                 &mp->process_handle);
-#endif
+#endif /* defined(_WIN32) */
 
   process_environment_free(env);
 
diff --git a/src/or/transports.h b/src/or/transports.h
index 44a9626e50..e368e447c3 100644
--- a/src/or/transports.h
+++ b/src/or/transports.h
@@ -133,7 +133,7 @@ STATIC char* get_pt_proxy_uri(void);
 
 STATIC void free_execve_args(char **arg);
 
-#endif
+#endif /* defined(PT_PRIVATE) */
 
-#endif
+#endif /* !defined(TOR_TRANSPORTS_H) */