Merge branch 'bug19180_easy_squashed'

78 files changed, 391 insertions, 289 deletions

diff --git a/src/common/address.c b/src/common/address.c
index 01607a4b3a..127e6a95bc 100644
--- a/src/common/address.c
+++ b/src/common/address.c
@@ -131,7 +131,8 @@ tor_addr_to_sockaddr(const tor_addr_t *a,
 #endif
     sin6->sin6_family = AF_INET6;
     sin6->sin6_port = htons(port);
-    memcpy(&sin6->sin6_addr, tor_addr_to_in6(a), sizeof(struct in6_addr));
+    memcpy(&sin6->sin6_addr, tor_addr_to_in6_assert(a),
+           sizeof(struct in6_addr));
     return sizeof(struct sockaddr_in6);
   } else {
     return 0;
diff --git a/src/common/address.h b/src/common/address.h
index 3de67e1c74..3f0bb521cd 100644
--- a/src/common/address.h
+++ b/src/common/address.h
@@ -74,6 +74,7 @@ typedef struct tor_addr_port_t
 #define TOR_ADDR_NULL {AF_UNSPEC, {0}}
 
 static inline const struct in6_addr *tor_addr_to_in6(const tor_addr_t *a);
+static inline const struct in6_addr *tor_addr_to_in6_assert(const tor_addr_t *a);
 static inline uint32_t tor_addr_to_ipv4n(const tor_addr_t *a);
 static inline uint32_t tor_addr_to_ipv4h(const tor_addr_t *a);
 static inline uint32_t tor_addr_to_mapped_ipv4h(const tor_addr_t *a);
@@ -97,21 +98,30 @@ tor_addr_to_in6(const tor_addr_t *a)
   return a->family == AF_INET6 ? &a->addr.in6_addr : NULL;
 }
 
+/** As tor_addr_to_in6, but assert that the address truly is an IPv6 address. */
+static inline const struct in6_addr *
+tor_addr_to_in6_assert(const tor_addr_t *a)
+{
+  tor_assert(a->family == AF_INET6);
+  return &a->addr.in6_addr;
+}
+
 /** Given an IPv6 address <b>x</b>, yield it as an array of uint8_t.
  *
  * Requires that <b>x</b> is actually an IPv6 address.
  */
-#define tor_addr_to_in6_addr8(x) tor_addr_to_in6(x)->s6_addr
+#define tor_addr_to_in6_addr8(x) tor_addr_to_in6_assert(x)->s6_addr
+
 /** Given an IPv6 address <b>x</b>, yield it as an array of uint16_t.
  *
  * Requires that <b>x</b> is actually an IPv6 address.
  */
-#define tor_addr_to_in6_addr16(x) S6_ADDR16(*tor_addr_to_in6(x))
+#define tor_addr_to_in6_addr16(x) S6_ADDR16(*tor_addr_to_in6_assert(x))
 /** Given an IPv6 address <b>x</b>, yield it as an array of uint32_t.
  *
  * Requires that <b>x</b> is actually an IPv6 address.
  */
-#define tor_addr_to_in6_addr32(x) S6_ADDR32(*tor_addr_to_in6(x))
+#define tor_addr_to_in6_addr32(x) S6_ADDR32(*tor_addr_to_in6_assert(x))
 
 /** Return an IPv4 address in network order for <b>a</b>, or 0 if
  * <b>a</b> is not an IPv4 address. */
diff --git a/src/common/compat.h b/src/common/compat.h
index b6ee4106db..6f102becc2 100644
--- a/src/common/compat.h
+++ b/src/common/compat.h
@@ -82,6 +82,44 @@
 #define CHECK_SCANF(formatIdx, firstArg)
 #endif
 
+/* What GCC do we have? */
+#ifdef __GNUC__
+#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+#else
+#define GCC_VERSION 0
+#endif
+
+/* Temporarily enable and disable warnings. */
+#ifdef __GNUC__
+#  define PRAGMA_STRINGIFY_(s) #s
+#  define PRAGMA_JOIN_STRINGIFY_(a,b) PRAGMA_STRINGIFY_(a ## b)
+/* Support for macro-generated pragmas (c99) */
+#  define PRAGMA_(x) _Pragma (#x)
+#  ifdef __clang__
+#    define PRAGMA_DIAGNOSTIC_(x) PRAGMA_(clang diagnostic x)
+#  else
+#    define PRAGMA_DIAGNOSTIC_(x) PRAGMA_(GCC diagnostic x)
+#  endif
+#  if defined(__clang__) || GCC_VERSION >= 406
+/* we have push/pop support */
+#    define DISABLE_GCC_WARNING(warning) \
+          PRAGMA_DIAGNOSTIC_(push) \
+          PRAGMA_DIAGNOSTIC_(ignored PRAGMA_JOIN_STRINGIFY_(-W,warning))
+#    define ENABLE_GCC_WARNING(warning) \
+          PRAGMA_DIAGNOSTIC_(pop)
+#  else
+/* older version of gcc: no push/pop support. */
+#    define DISABLE_GCC_WARNING(warning) \
+         PRAGMA_DIAGNOSTIC_(ignored PRAGMA_JOIN_STRINGIFY_(-W,warning))
+#    define ENABLE_GCC_WARNING(warning) \
+         PRAGMA_DIAGNOSTIC_(warning PRAGMA_JOIN_STRINGIFY_(-W,warning))
+#  endif
+#else /* ifdef __GNUC__ */
+/* not gcc at all */
+# define DISABLE_GCC_WARNING(warning)
+# define ENABLE_GCC_WARNING(warning)
+#endif
+
 /* inline is __inline on windows. */
 #ifdef _WIN32
 #define inline __inline
diff --git a/src/common/compat_libevent.c b/src/common/compat_libevent.c
index cc58883750..96fcec54d4 100644
--- a/src/common/compat_libevent.c
+++ b/src/common/compat_libevent.c
@@ -125,7 +125,7 @@ tor_event_free(struct event *ev)
 #endif
 
 /** Global event base for use by the main thread. */
-struct event_base *the_event_base = NULL;
+static struct event_base *the_event_base = NULL;
 
 /* This is what passes for version detection on OSX.  We set
  * MACOSX_KQUEUE_IS_BROKEN to true iff we're on a version of OSX before
diff --git a/src/common/crypto.h b/src/common/crypto.h
index ff38cca0da..f8fb0daa81 100644
--- a/src/common/crypto.h
+++ b/src/common/crypto.h
@@ -319,6 +319,11 @@ void crypto_add_spaces_to_fp(char *out, size_t outlen, const char *in);
 #ifdef CRYPTO_PRIVATE
 STATIC int crypto_force_rand_ssleay(void);
 STATIC int crypto_strongest_rand_raw(uint8_t *out, size_t out_len);
+
+#ifdef TOR_UNIT_TESTS
+extern int break_strongest_rng_syscall;
+extern int break_strongest_rng_fallback;
+#endif
 #endif
 
 #endif
diff --git a/src/common/log.c b/src/common/log.c
index 6c387c6244..e948ccfa04 100644
--- a/src/common/log.c
+++ b/src/common/log.c
@@ -270,7 +270,7 @@ log_tor_version(logfile_t *lf, int reset)
   return 0;
 }
 
-const char bug_suffix[] = " (on Tor " VERSION
+static const char bug_suffix[] = " (on Tor " VERSION
 #ifndef _MSC_VER
   " "
 #include "micro-revision.i"
diff --git a/src/common/sandbox.c b/src/common/sandbox.c
index 70c5bbd07c..4e2c5cde22 100644
--- a/src/common/sandbox.c
+++ b/src/common/sandbox.c
@@ -1443,7 +1443,7 @@ static HT_HEAD(getaddrinfo_cache, cached_getaddrinfo_item_t)
 
 HT_PROTOTYPE(getaddrinfo_cache, cached_getaddrinfo_item_t, node,
              cached_getaddrinfo_item_hash,
-             cached_getaddrinfo_items_eq);
+             cached_getaddrinfo_items_eq)
 HT_GENERATE2(getaddrinfo_cache, cached_getaddrinfo_item_t, node,
              cached_getaddrinfo_item_hash,
              cached_getaddrinfo_items_eq,
diff --git a/src/common/torlog.h b/src/common/torlog.h
index 578af7caea..80f37e0e48 100644
--- a/src/common/torlog.h
+++ b/src/common/torlog.h
@@ -176,7 +176,7 @@ void log_fn_ratelim_(struct ratelim_t *ratelim, int severity,
                      const char *format, ...)
   CHECK_PRINTF(5,6);
 
-#if defined(__GNUC__)
+#if defined(__GNUC__) && __GNUC__ <= 3
 
 /* These are the GCC varidaic macros, so that older versions of GCC don't
  * break. */
diff --git a/src/common/tortls.c b/src/common/tortls.c
index 4ffc672546..1cb6ca8777 100644
--- a/src/common/tortls.c
+++ b/src/common/tortls.c
@@ -24,18 +24,11 @@
   #include <ws2tcpip.h>
 #endif
 
-#ifdef __GNUC__
-#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
-#endif
+#include "compat.h"
 
-#if __GNUC__ && GCC_VERSION >= 402
-#if GCC_VERSION >= 406
-#pragma GCC diagnostic push
-#endif
 /* Some versions of OpenSSL declare SSL_get_selected_srtp_profile twice in
  * srtp.h. Suppress the GCC warning so we can build with -Wredundant-decl. */
-#pragma GCC diagnostic ignored "-Wredundant-decls"
-#endif
+DISABLE_GCC_WARNING(redundant-decls)
 
 #include <openssl/opensslv.h>
 #include "crypto.h"
@@ -53,13 +46,7 @@
 #include <openssl/bn.h>
 #include <openssl/rsa.h>
 
-#if __GNUC__ && GCC_VERSION >= 402
-#if GCC_VERSION >= 406
-#pragma GCC diagnostic pop
-#else
-#pragma GCC diagnostic warning "-Wredundant-decls"
-#endif
-#endif
+ENABLE_GCC_WARNING(redundant-decls)
 
 #ifdef USE_BUFFEREVENTS
 #include <event2/bufferevent_ssl.h>
@@ -575,7 +562,7 @@ MOCK_IMPL(STATIC X509 *,
 
 /** List of ciphers that servers should select from when we actually have
  * our choice of what cipher to use. */
-const char UNRESTRICTED_SERVER_CIPHER_LIST[] =
+static const char UNRESTRICTED_SERVER_CIPHER_LIST[] =
   /* This list is autogenerated with the gen_server_ciphers.py script;
    * don't hand-edit it. */
 #ifdef TLS1_TXT_ECDHE_RSA_WITH_AES_256_GCM_SHA384
diff --git a/src/common/tortls.h b/src/common/tortls.h
index 1a59c67df3..b6ab2ec8f5 100644
--- a/src/common/tortls.h
+++ b/src/common/tortls.h
@@ -164,8 +164,18 @@ STATIC int tor_tls_context_init_one(tor_tls_context_t **ppcontext,
                                     int is_client);
 STATIC void tls_log_errors(tor_tls_t *tls, int severity, int domain,
                            const char *doing);
+
+#ifdef TOR_UNIT_TESTS
+extern int tor_tls_object_ex_data_index;
+extern tor_tls_context_t *server_tls_context;
+extern tor_tls_context_t *client_tls_context;
+extern uint16_t v2_cipher_list[];
+extern uint64_t total_bytes_written_over_tls;
+extern uint64_t total_bytes_written_by_tls;
 #endif
 
+#endif /* endif TORTLS_PRIVATE */
+
 const char *tor_tls_err_to_string(int err);
 void tor_tls_get_state_description(tor_tls_t *tls, char *buf, size_t sz);
 
diff --git a/src/common/util.c b/src/common/util.c
index 78afe5954f..1546fd123d 100644
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -342,6 +342,7 @@ tor_free_(void *mem)
   tor_free(mem);
 }
 
+DISABLE_GCC_WARNING(aggregate-return)
 /** Call the platform malloc info function, and dump the results to the log at
  * level <b>severity</b>.  If no such function exists, do nothing. */
 void
@@ -369,6 +370,7 @@ tor_log_mallinfo(int severity)
                       );
 #endif
 }
+ENABLE_GCC_WARNING(aggregate-return)
 
 /* =====
  * Math
@@ -5528,7 +5530,7 @@ clamp_double_to_int64(double number)
    * representable integer for which this is not the case is INT64_MIN, but
    * it is covered by the logic below. */
   if (isfinite(number) && exp <= 63) {
-    return number;
+    return (int64_t)number;
   }
 
   /* Handle infinities and finite numbers with magnitude >= 2^63. */
diff --git a/src/common/util_process.c b/src/common/util_process.c
index 848b238318..abda63720c 100644
--- a/src/common/util_process.c
+++ b/src/common/util_process.c
@@ -61,9 +61,9 @@ process_map_entries_eq_(const waitpid_callback_t *a,
 static HT_HEAD(process_map, waitpid_callback_t) process_map = HT_INITIALIZER();
 
 HT_PROTOTYPE(process_map, waitpid_callback_t, node, process_map_entry_hash_,
-             process_map_entries_eq_);
+             process_map_entries_eq_)
 HT_GENERATE2(process_map, waitpid_callback_t, node, process_map_entry_hash_,
-             process_map_entries_eq_, 0.6, tor_reallocarray_, tor_free_);
+             process_map_entries_eq_, 0.6, tor_reallocarray_, tor_free_)
 
 /**
  * Begin monitoring the child pid <b>pid</b> to see if we get a SIGCHLD for
diff --git a/src/ext/ed25519/donna/curve25519-donna-64bit.h b/src/ext/ed25519/donna/curve25519-donna-64bit.h
index 2941d1bcdc..50c9916768 100644
--- a/src/ext/ed25519/donna/curve25519-donna-64bit.h
+++ b/src/ext/ed25519/donna/curve25519-donna-64bit.h
@@ -8,9 +8,9 @@
 
 typedef uint64_t bignum25519[5];
 
-static const uint64_t reduce_mask_40 = ((uint64_t)1 << 40) - 1;
+//static const uint64_t reduce_mask_40 = ((uint64_t)1 << 40) - 1;
 static const uint64_t reduce_mask_51 = ((uint64_t)1 << 51) - 1;
-static const uint64_t reduce_mask_56 = ((uint64_t)1 << 56) - 1;
+//static const uint64_t reduce_mask_56 = ((uint64_t)1 << 56) - 1;
 
 /* out = in */
 DONNA_INLINE static void
diff --git a/src/ext/ed25519/donna/ed25519-donna-64bit-x86.h b/src/ext/ed25519/donna/ed25519-donna-64bit-x86.h
index 30bd472762..f6b5570298 100644
--- a/src/ext/ed25519/donna/ed25519-donna-64bit-x86.h
+++ b/src/ext/ed25519/donna/ed25519-donna-64bit-x86.h
@@ -2,6 +2,11 @@
 
 #define HAVE_GE25519_SCALARMULT_BASE_CHOOSE_NIELS
 
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Woverlength-strings"
+#endif
+
 DONNA_NOINLINE static void
 ge25519_scalarmult_base_choose_niels(ge25519_niels *t, const uint8_t table[256][96], uint32_t pos, signed char b) {
 	int64_t breg = (int64_t)b;
@@ -347,5 +352,9 @@ ge25519_scalarmult_base_choose_niels(ge25519_niels *t, const uint8_t table[256][
 	);
 }
 
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
 #endif /* defined(ED25519_GCC_64BIT_X86_CHOOSE) */
 
diff --git a/src/ext/ed25519/donna/ed25519-donna-batchverify.h b/src/ext/ed25519/donna/ed25519-donna-batchverify.h
index 43c4923b3e..7c64cce787 100644
--- a/src/ext/ed25519/donna/ed25519-donna-batchverify.h
+++ b/src/ext/ed25519/donna/ed25519-donna-batchverify.h
@@ -188,7 +188,7 @@ ge25519_multi_scalarmult_vartime(ge25519 *r, batch_heap *heap, size_t count) {
 }
 
 /* not actually used for anything other than testing */
-unsigned char batch_point_buffer[3][32];
+static unsigned char batch_point_buffer[3][32];
 
 static int
 ge25519_is_neutral_vartime(const ge25519 *p) {
diff --git a/src/ext/ht.h b/src/ext/ht.h
index 28d1fe49d5..1b6cbe6632 100644
--- a/src/ext/ht.h
+++ b/src/ext/ht.h
@@ -203,6 +203,7 @@ ht_string_hash(const char *s)
       name##_HT_GROW(head, head->hth_n_entries+1);                      \
     HT_SET_HASH_(elm, field, hashfn);                                   \
     p = name##_HT_FIND_P_(head, elm);                                   \
+    HT_ASSERT_(p != NULL); /* this holds because we called HT_GROW */   \
     r = *p;                                                             \
     *p = elm;                                                           \
     if (r && (r!=elm)) {                                                \
@@ -470,6 +471,7 @@ ht_string_hash(const char *s)
       name##_HT_GROW(var##_head_, var##_head_->hth_n_entries+1);        \
     HT_SET_HASH_((elm), field, hashfn);                                 \
     var = name##_HT_FIND_P_(var##_head_, (elm));                        \
+    HT_ASSERT_(var); /* Holds because we called HT_GROW */              \
     if (*var) {                                                         \
       y;                                                                \
     } else {                                                            \
diff --git a/src/ext/tinytest.c b/src/ext/tinytest.c
index f6baeeb9a5..3fb1b39c71 100644
--- a/src/ext/tinytest.c
+++ b/src/ext/tinytest.c
@@ -69,15 +69,16 @@ static int n_skipped = 0; /**< Number of tests that have been skipped. */
 static int opt_forked = 0; /**< True iff we're called from inside a win32 fork*/
 static int opt_nofork = 0; /**< Suppress calls to fork() for debugging. */
 static int opt_verbosity = 1; /**< -==quiet,0==terse,1==normal,2==verbose */
-const char *verbosity_flag = "";
+static const char *verbosity_flag = "";
 
-const struct testlist_alias_t *cfg_aliases=NULL;
+static const struct testlist_alias_t *cfg_aliases=NULL;
 
 enum outcome { SKIP=2, OK=1, FAIL=0 };
 static enum outcome cur_test_outcome = 0;
-const char *cur_test_prefix = NULL; /**< prefix of the current test group */
+/** prefix of the current test group */
+static const char *cur_test_prefix = NULL;
 /** Name of the current test, if we haven't logged is yet. Used for --quiet */
-const char *cur_test_name = NULL;
+static const char *cur_test_name = NULL;
 
 #ifdef _WIN32
 /* Copy of argv[0] for win32. */
diff --git a/src/or/channel.c b/src/or/channel.c
index f3939399b0..87fa721089 100644
--- a/src/or/channel.c
+++ b/src/or/channel.c
@@ -122,7 +122,7 @@ STATIC uint64_t estimated_total_queue_size = 0;
  * If more than one channel exists, follow the next_with_same_id pointer
  * as a linked list.
  */
-HT_HEAD(channel_idmap, channel_idmap_entry_s) channel_identity_map =
+static HT_HEAD(channel_idmap, channel_idmap_entry_s) channel_identity_map =
   HT_INITIALIZER();
 
 typedef struct channel_idmap_entry_s {
@@ -145,9 +145,9 @@ channel_idmap_eq(const channel_idmap_entry_t *a,
 }
 
 HT_PROTOTYPE(channel_idmap, channel_idmap_entry_s, node, channel_idmap_hash,
-             channel_idmap_eq);
+             channel_idmap_eq)
 HT_GENERATE2(channel_idmap, channel_idmap_entry_s, node, channel_idmap_hash,
-             channel_idmap_eq, 0.5,  tor_reallocarray_, tor_free_);
+             channel_idmap_eq, 0.5,  tor_reallocarray_, tor_free_)
 
 static cell_queue_entry_t * cell_queue_entry_dup(cell_queue_entry_t *q);
 #if 0
@@ -4524,8 +4524,8 @@ channel_update_xmit_queue_size(channel_t *chan)
   /* Next, adjust by the overhead factor, if any is available */
   if (chan->get_overhead_estimate) {
     overhead = chan->get_overhead_estimate(chan);
-    if (overhead >= 1.0f) {
-      queued *= overhead;
+    if (overhead >= 1.0) {
+      queued = (uint64_t)(queued * overhead);
     } else {
       /* Ignore silly overhead factors */
       log_notice(LD_CHANNEL, "Ignoring silly overhead factor %f", overhead);
diff --git a/src/or/channel.h b/src/or/channel.h
index a8c337e107..78e1b71014 100644
--- a/src/or/channel.h
+++ b/src/or/channel.h
@@ -469,6 +469,10 @@ void channel_notify_flushed(channel_t *chan);
 /* Handle stuff we need to do on open like notifying circuits */
 void channel_do_open_actions(channel_t *chan);
 
+#ifdef TOR_UNIT_TESTS
+extern uint64_t estimated_total_queue_size;
+#endif
+
 #endif
 
 /* Helper functions to perform operations on channels */
diff --git a/src/or/channeltls.c b/src/or/channeltls.c
index 2128b0924d..2bb88dd505 100644
--- a/src/or/channeltls.c
+++ b/src/or/channeltls.c
@@ -22,6 +22,7 @@
 #include "channeltls.h"
 #include "circuitmux.h"
 #include "circuitmux_ewma.h"
+#include "command.h"
 #include "config.h"
 #include "connection.h"
 #include "connection_or.h"
@@ -51,7 +52,7 @@ uint64_t stats_n_authenticate_cells_processed = 0;
 uint64_t stats_n_authorize_cells_processed = 0;
 
 /** Active listener, if any */
-channel_listener_t *channel_tls_listener = NULL;
+static channel_listener_t *channel_tls_listener = NULL;
 
 /* channel_tls_t method declarations */
 
@@ -445,7 +446,7 @@ channel_tls_free_method(channel_t *chan)
 static double
 channel_tls_get_overhead_estimate_method(channel_t *chan)
 {
-  double overhead = 1.0f;
+  double overhead = 1.0;
   channel_tls_t *tlschan = BASE_CHAN_TO_TLS(chan);
 
   tor_assert(tlschan);
@@ -462,7 +463,8 @@ channel_tls_get_overhead_estimate_method(channel_t *chan)
      * Never estimate more than 2.0; otherwise we get silly large estimates
      * at the very start of a new TLS connection.
      */
-    if (overhead > 2.0f) overhead = 2.0f;
+    if (overhead > 2.0)
+      overhead = 2.0;
   }
 
   log_debug(LD_CHANNEL,
@@ -797,6 +799,7 @@ static int
 channel_tls_write_packed_cell_method(channel_t *chan,
                                      packed_cell_t *packed_cell)
 {
+  tor_assert(chan);
   channel_tls_t *tlschan = BASE_CHAN_TO_TLS(chan);
   size_t cell_network_size = get_cell_network_size(chan->wide_circ_ids);
   int written = 0;
diff --git a/src/or/channeltls.h b/src/or/channeltls.h
index a4d9c7a095..8b5863a461 100644
--- a/src/or/channeltls.h
+++ b/src/or/channeltls.h
@@ -52,6 +52,14 @@ void channel_tls_update_marks(or_connection_t *conn);
 /* Cleanup at shutdown */
 void channel_tls_free_all(void);
 
+extern uint64_t stats_n_authorize_cells_processed;
+extern uint64_t stats_n_authenticate_cells_processed;
+extern uint64_t stats_n_versions_cells_processed;
+extern uint64_t stats_n_netinfo_cells_processed;
+extern uint64_t stats_n_vpadding_cells_processed;
+extern uint64_t stats_n_certs_cells_processed;
+extern uint64_t stats_n_auth_challenge_cells_processed;
+
 #ifdef CHANNELTLS_PRIVATE
 STATIC void channel_tls_process_certs_cell(var_cell_t *cell,
                                            channel_tls_t *tlschan);
diff --git a/src/or/circuitlist.c b/src/or/circuitlist.c
index 1efb7ef4d0..d2ba7d4781 100644
--- a/src/or/circuitlist.c
+++ b/src/or/circuitlist.c
@@ -109,7 +109,7 @@ HT_GENERATE2(chan_circid_map, chan_circid_circuit_map_t, node,
  * used to improve performance when many cells arrive in a row from the
  * same circuit.
  */
-chan_circid_circuit_map_t *_last_circid_chan_ent = NULL;
+static chan_circid_circuit_map_t *_last_circid_chan_ent = NULL;
 
 /** Implementation helper for circuit_set_{p,n}_circid_channel: A circuit ID
  * and/or channel for circ has just changed from <b>old_chan, old_id</b>
diff --git a/src/or/circuitmux.c b/src/or/circuitmux.c
index cc1c4cd401..038904e68a 100644
--- a/src/or/circuitmux.c
+++ b/src/or/circuitmux.c
@@ -362,7 +362,7 @@ HT_HEAD(chanid_circid_muxinfo_map, chanid_circid_muxinfo_t);
 
 /* Emit a bunch of hash table stuff */
 HT_PROTOTYPE(chanid_circid_muxinfo_map, chanid_circid_muxinfo_t, node,
-             chanid_circid_entry_hash, chanid_circid_entries_eq);
+             chanid_circid_entry_hash, chanid_circid_entries_eq)
 HT_GENERATE2(chanid_circid_muxinfo_map, chanid_circid_muxinfo_t, node,
              chanid_circid_entry_hash, chanid_circid_entries_eq, 0.6,
              tor_reallocarray_, tor_free_)
diff --git a/src/or/circuitmux_ewma.h b/src/or/circuitmux_ewma.h
index 58aac1e196..a7b8961ac6 100644
--- a/src/or/circuitmux_ewma.h
+++ b/src/or/circuitmux_ewma.h
@@ -12,13 +12,8 @@
 #include "or.h"
 #include "circuitmux.h"
 
-/* Everything but circuitmux_ewma.c should see this extern */
-#ifndef TOR_CIRCUITMUX_EWMA_C_
-
 extern circuitmux_policy_t ewma_policy;
 
-#endif /* !(TOR_CIRCUITMUX_EWMA_C_) */
-
 /* Externally visible EWMA functions */
 int cell_ewma_enabled(void);
 unsigned int cell_ewma_get_tick(void);
diff --git a/src/or/config.c b/src/or/config.c
index b9e8700b4f..8a3fb47790 100644
--- a/src/or/config.c
+++ b/src/or/config.c
@@ -65,9 +65,6 @@
 #include <systemd/sd-daemon.h>
 #endif
 
-/* From main.c */
-extern int quiet_level;
-
 /* Prefix used to indicate a Unix socket in a FooPort configuration. */
 static const char unix_socket_prefix[] = "unix:";
 
@@ -2677,7 +2674,7 @@ options_validate_cb(void *old_options, void *options, void *default_options,
 
 #define REJECT(arg) \
   STMT_BEGIN *msg = tor_strdup(arg); return -1; STMT_END
-#ifdef __GNUC__
+#if defined(__GNUC__) && __GNUC__ <= 3
 #define COMPLAIN(args...) \
   STMT_BEGIN log_warn(LD_CONFIG, args); STMT_END
 #else
@@ -5776,7 +5773,7 @@ parse_dir_authority_line(const char *line, dirinfo_type_t required_type,
     } else if (!strcmpstart(flag, "weight=")) {
       int ok;
       const char *wstring = flag + strlen("weight=");
-      weight = tor_parse_double(wstring, 0, UINT64_MAX, &ok, NULL);
+      weight = tor_parse_double(wstring, 0, (double)UINT64_MAX, &ok, NULL);
       if (!ok) {
         log_warn(LD_CONFIG, "Invalid weight '%s' on DirAuthority line.",flag);
         weight=1.0;
@@ -5920,7 +5917,7 @@ parse_dir_fallback_line(const char *line,
     } else if (!strcmpstart(cp, "weight=")) {
       int ok;
       const char *wstring = cp + strlen("weight=");
-      weight = tor_parse_double(wstring, 0, UINT64_MAX, &ok, NULL);
+      weight = tor_parse_double(wstring, 0, (double)UINT64_MAX, &ok, NULL);
       if (!ok) {
         log_warn(LD_CONFIG, "Invalid weight '%s' on FallbackDir line.", cp);
         weight=1.0;
diff --git a/src/or/confparse.c b/src/or/confparse.c
index 4f446d07c3..3532b39d93 100644
--- a/src/or/confparse.c
+++ b/src/or/confparse.c
@@ -1238,7 +1238,7 @@ config_parse_units(const char *val, struct unit_table_t *u, int *ok)
 
   v = tor_parse_uint64(val, 10, 0, UINT64_MAX, ok, &cp);
   if (!*ok || (cp && *cp == '.')) {
-    d = tor_parse_double(val, 0, UINT64_MAX, ok, &cp);
+    d = tor_parse_double(val, 0, (double)UINT64_MAX, ok, &cp);
     if (!*ok)
       goto done;
     use_float = 1;
@@ -1255,7 +1255,7 @@ config_parse_units(const char *val, struct unit_table_t *u, int *ok)
   for ( ;u->unit;++u) {
     if (!strcasecmp(u->unit, cp)) {
       if (use_float)
-        v = u->multiplier * d;
+        v = (uint64_t)(u->multiplier * d);
       else
         v *= u->multiplier;
       *ok = 1;
diff --git a/src/or/connection.c b/src/or/connection.c
index 9362cf28fe..9eef063f18 100644
--- a/src/or/connection.c
+++ b/src/or/connection.c
@@ -2240,7 +2240,7 @@ connection_send_socks5_connect(connection_t *conn)
   } else { /* AF_INET6 */
     buf[3] = 4;
     reqsize += 16;
-    memcpy(buf + 4, tor_addr_to_in6(&conn->addr), 16);
+    memcpy(buf + 4, tor_addr_to_in6_addr8(&conn->addr), 16);
     memcpy(buf + 20, &port, 2);
   }
 
@@ -2697,8 +2697,6 @@ connection_is_rate_limited(connection_t *conn)
 #ifdef USE_BUFFEREVENTS
 static struct bufferevent_rate_limit_group *global_rate_limit = NULL;
 #else
-extern int global_read_bucket, global_write_bucket;
-extern int global_relayed_read_bucket, global_relayed_write_bucket;
 
 /** Did either global write bucket run dry last second? If so,
  * we are likely to run dry again this second, so be stingy with the
diff --git a/src/or/dircollate.c b/src/or/dircollate.c
index 3f9d78f02d..756011b934 100644
--- a/src/or/dircollate.c
+++ b/src/or/dircollate.c
@@ -67,9 +67,9 @@ ddmap_entry_set_digests(ddmap_entry_t *ent,
 }
 
 HT_PROTOTYPE(double_digest_map, ddmap_entry_s, node, ddmap_entry_hash,
-             ddmap_entry_eq);
+             ddmap_entry_eq)
 HT_GENERATE2(double_digest_map, ddmap_entry_s, node, ddmap_entry_hash,
-             ddmap_entry_eq, 0.6, tor_reallocarray, tor_free_);
+             ddmap_entry_eq, 0.6, tor_reallocarray, tor_free_)
 
 /** Helper: add a single vote_routerstatus_t <b>vrs</b> to the collator
  * <b>dc</b>, indexing it by its RSA key digest, and by the 2-tuple of
diff --git a/src/or/dirserv.c b/src/or/dirserv.c
index ad476c582a..fa698701c3 100644
--- a/src/or/dirserv.c
+++ b/src/or/dirserv.c
@@ -19,6 +19,7 @@
 #include "dirvote.h"
 #include "hibernate.h"
 #include "keypin.h"
+#include "main.h"
 #include "microdesc.h"
 #include "networkstatus.h"
 #include "nodelist.h"
@@ -44,10 +45,6 @@
  * directory authorities. */
 #define MAX_UNTRUSTED_NETWORKSTATUSES 16
 
-extern time_t time_of_process_start; /* from main.c */
-
-extern long stats_n_seconds_working; /* from main.c */
-
 /** Total number of routers with measured bandwidth; this is set by
  * dirserv_count_measured_bws() before the loop in
  * dirserv_generate_networkstatus_vote_obj() and checked by
diff --git a/src/or/geoip.c b/src/or/geoip.c
index b563db0418..874052495e 100644
--- a/src/or/geoip.c
+++ b/src/or/geoip.c
@@ -80,9 +80,9 @@ geoip_add_entry(const tor_addr_t *low, const tor_addr_t *high,
   intptr_t idx;
   void *idxplus1_;
 
-  if (tor_addr_family(low) != tor_addr_family(high))
+  IF_BUG_ONCE(tor_addr_family(low) != tor_addr_family(high))
     return;
-  if (tor_addr_compare(high, low, CMP_EXACT) < 0)
+  IF_BUG_ONCE(tor_addr_compare(high, low, CMP_EXACT) < 0)
     return;
 
   idxplus1_ = strmap_get_lc(country_idxplus1_by_lc_code, country);
@@ -110,8 +110,8 @@ geoip_add_entry(const tor_addr_t *low, const tor_addr_t *high,
     smartlist_add(geoip_ipv4_entries, ent);
   } else if (tor_addr_family(low) == AF_INET6) {
     geoip_ipv6_entry_t *ent = tor_malloc_zero(sizeof(geoip_ipv6_entry_t));
-    ent->ip_low = *tor_addr_to_in6(low);
-    ent->ip_high = *tor_addr_to_in6(high);
+    ent->ip_low = *tor_addr_to_in6_assert(low);
+    ent->ip_high = *tor_addr_to_in6_assert(high);
     ent->country = idx;
     smartlist_add(geoip_ipv6_entries, ent);
   }
@@ -504,7 +504,7 @@ clientmap_entries_eq(const clientmap_entry_t *a, const clientmap_entry_t *b)
 }
 
 HT_PROTOTYPE(clientmap, clientmap_entry_t, node, clientmap_entry_hash,
-             clientmap_entries_eq);
+             clientmap_entries_eq)
 HT_GENERATE2(clientmap, clientmap_entry_t, node, clientmap_entry_hash,
              clientmap_entries_eq, 0.6, tor_reallocarray_, tor_free_)
 
@@ -718,7 +718,7 @@ dirreq_map_ent_hash(const dirreq_map_entry_t *entry)
 }
 
 HT_PROTOTYPE(dirreqmap, dirreq_map_entry_t, node, dirreq_map_ent_hash,
-             dirreq_map_ent_eq);
+             dirreq_map_ent_eq)
 HT_GENERATE2(dirreqmap, dirreq_map_entry_t, node, dirreq_map_ent_hash,
              dirreq_map_ent_eq, 0.6, tor_reallocarray_, tor_free_)
 
diff --git a/src/or/hibernate.c b/src/or/hibernate.c
index 3666abbcf4..209aae01cf 100644
--- a/src/or/hibernate.c
+++ b/src/or/hibernate.c
@@ -34,8 +34,6 @@ hibernating, phase 2:
 #include "router.h"
 #include "statefile.h"
 
-extern long stats_n_seconds_working; /* published uptime */
-
 /** Are we currently awake, asleep, running out of bandwidth, or shutting
  * down? */
 static hibernate_state_t hibernate_state = HIBERNATE_STATE_INITIAL;
diff --git a/src/or/keypin.c b/src/or/keypin.c
index 1f82eccf86..749bc6121c 100644
--- a/src/or/keypin.c
+++ b/src/or/keypin.c
@@ -93,14 +93,14 @@ return (unsigned) siphash24g(a->ed25519_key, sizeof(a->ed25519_key));
 }
 
 HT_PROTOTYPE(rsamap, keypin_ent_st, rsamap_node, keypin_ent_hash_rsa,
-               keypin_ents_eq_rsa);
+               keypin_ents_eq_rsa)
 HT_GENERATE2(rsamap, keypin_ent_st, rsamap_node, keypin_ent_hash_rsa,
-               keypin_ents_eq_rsa, 0.6, tor_reallocarray, tor_free_);
+               keypin_ents_eq_rsa, 0.6, tor_reallocarray, tor_free_)
 
 HT_PROTOTYPE(edmap, keypin_ent_st, edmap_node, keypin_ent_hash_ed,
-               keypin_ents_eq_ed);
+               keypin_ents_eq_ed)
 HT_GENERATE2(edmap, keypin_ent_st, edmap_node, keypin_ent_hash_ed,
-               keypin_ents_eq_ed, 0.6, tor_reallocarray, tor_free_);
+               keypin_ents_eq_ed, 0.6, tor_reallocarray, tor_free_)
 
 /**
  * Check whether we already have an entry in the key pinning table for a
diff --git a/src/or/main.c b/src/or/main.c
index ac477da66c..9f3306dc4f 100644
--- a/src/or/main.c
+++ b/src/or/main.c
@@ -2683,9 +2683,6 @@ get_uptime,(void))
   return stats_n_seconds_working;
 }
 
-extern uint64_t rephist_total_alloc;
-extern uint32_t rephist_total_num;
-
 /**
  * Write current memory usage information to the log.
  */
diff --git a/src/or/main.h b/src/or/main.h
index ad865b8124..31a22de424 100644
--- a/src/or/main.h
+++ b/src/or/main.h
@@ -75,6 +75,14 @@ int tor_main(int argc, char *argv[]);
 int do_main_loop(void);
 int tor_init(int argc, char **argv);
 
+extern time_t time_of_process_start;
+extern long stats_n_seconds_working;
+extern int quiet_level;
+extern int global_read_bucket;
+extern int global_write_bucket;
+extern int global_relayed_read_bucket;
+extern int global_relayed_write_bucket;
+
 #ifdef MAIN_PRIVATE
 STATIC void init_connection_lists(void);
 STATIC void close_closeable_connections(void);
diff --git a/src/or/microdesc.c b/src/or/microdesc.c
index f3788f4209..130259a29f 100644
--- a/src/or/microdesc.c
+++ b/src/or/microdesc.c
@@ -69,7 +69,7 @@ microdesc_eq_(microdesc_t *a, microdesc_t *b)
 }
 
 HT_PROTOTYPE(microdesc_map, microdesc_t, node,
-             microdesc_hash_, microdesc_eq_);
+             microdesc_hash_, microdesc_eq_)
 HT_GENERATE2(microdesc_map, microdesc_t, node,
              microdesc_hash_, microdesc_eq_, 0.6,
              tor_reallocarray_, tor_free_)
diff --git a/src/or/nodelist.c b/src/or/nodelist.c
index abbb82dfdd..a49bf03f61 100644
--- a/src/or/nodelist.c
+++ b/src/or/nodelist.c
@@ -77,7 +77,7 @@ node_id_eq(const node_t *node1, const node_t *node2)
   return tor_memeq(node1->identity, node2->identity, DIGEST_LEN);
 }
 
-HT_PROTOTYPE(nodelist_map, node_t, ht_ent, node_id_hash, node_id_eq);
+HT_PROTOTYPE(nodelist_map, node_t, ht_ent, node_id_hash, node_id_eq)
 HT_GENERATE2(nodelist_map, node_t, ht_ent, node_id_hash, node_id_eq,
              0.6, tor_reallocarray_, tor_free_)
 
@@ -594,10 +594,10 @@ node_get_by_nickname,(const char *nickname, int warn_if_unnamed))
                  "but none is listed as Named in the directory consensus. "
                  "Choosing one arbitrarily.", nickname);
       }
-    } else if (smartlist_len(matches)>1 && warn_if_unnamed) {
+    } else if (smartlist_len(matches)==1 && warn_if_unnamed) {
       char fp[HEX_DIGEST_LEN+1];
       node_t *node = smartlist_get(matches, 0);
-      if (node->name_lookup_warned) {
+      if (! node->name_lookup_warned) {
         base16_encode(fp, sizeof(fp), node->identity, DIGEST_LEN);
         log_warn(LD_CONFIG,
                  "You specified a server \"%s\" by name, but the directory "
diff --git a/src/or/onion.c b/src/or/onion.c
index 944506e3af..28b9787048 100644
--- a/src/or/onion.c
+++ b/src/or/onion.c
@@ -38,7 +38,7 @@ typedef struct onion_queue_t {
 
 /** Array of queues of circuits waiting for CPU workers. An element is NULL
  * if that queue is empty.*/
-TOR_TAILQ_HEAD(onion_queue_head_t, onion_queue_t)
+static TOR_TAILQ_HEAD(onion_queue_head_t, onion_queue_t)
               ol_list[MAX_ONION_HANDSHAKE_TYPE+1] = {
   TOR_TAILQ_HEAD_INITIALIZER(ol_list[0]), /* tap */
   TOR_TAILQ_HEAD_INITIALIZER(ol_list[1]), /* fast */
diff --git a/src/or/onion_ntor.c b/src/or/onion_ntor.c
index 9f97a4cfbe..33afc27895 100644
--- a/src/or/onion_ntor.c
+++ b/src/or/onion_ntor.c
@@ -47,7 +47,7 @@ typedef struct tweakset_t {
 } tweakset_t;
 
 /** The tweaks to be used with our handshake. */
-const tweakset_t proto1_tweaks = {
+static const tweakset_t proto1_tweaks = {
 #define PROTOID "ntor-curve25519-sha256-1"
 #define PROTOID_LEN 24
   PROTOID ":mac",
diff --git a/src/or/rendcache.h b/src/or/rendcache.h
index 0e8b918753..270b614c38 100644
--- a/src/or/rendcache.h
+++ b/src/or/rendcache.h
@@ -102,6 +102,13 @@ STATIC void validate_intro_point_failure(const rend_service_descriptor_t *desc,
                                         const char *service_id);
 
 STATIC void rend_cache_failure_entry_free_(void *entry);
+
+#ifdef TOR_UNIT_TESTS
+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 /* TOR_RENDCACHE_H */
diff --git a/src/or/rephist.c b/src/or/rephist.c
index 8156e078b9..72933550ed 100644
--- a/src/or/rephist.c
+++ b/src/or/rephist.c
@@ -2738,7 +2738,7 @@ bidi_map_ent_hash(const bidi_map_entry_t *entry)
 }
 
 HT_PROTOTYPE(bidimap, bidi_map_entry_t, node, bidi_map_ent_hash,
-             bidi_map_ent_eq);
+             bidi_map_ent_eq)
 HT_GENERATE2(bidimap, bidi_map_entry_t, node, bidi_map_ent_hash,
              bidi_map_ent_eq, 0.6, tor_reallocarray_, tor_free_)
 
diff --git a/src/or/rephist.h b/src/or/rephist.h
index 145da97d02..ff4810a56d 100644
--- a/src/or/rephist.h
+++ b/src/or/rephist.h
@@ -112,5 +112,12 @@ void rep_hist_note_negotiated_link_proto(unsigned link_proto,
                                          int started_here);
 void rep_hist_log_link_protocol_counts(void);
 
+extern uint64_t rephist_total_alloc;
+extern uint32_t rephist_total_num;
+#ifdef TOR_UNIT_TESTS
+extern int onion_handshakes_requested[MAX_ONION_HANDSHAKE_TYPE+1];
+extern int onion_handshakes_assigned[MAX_ONION_HANDSHAKE_TYPE+1];
+#endif
+
 #endif
 
diff --git a/src/or/router.c b/src/or/router.c
index 779cbb7bb0..a671591ad7 100644
--- a/src/or/router.c
+++ b/src/or/router.c
@@ -40,8 +40,6 @@
  * and uploading server descriptors, retrying OR connections.
  **/
 
-extern long stats_n_seconds_working;
-
 /************************************************************/
 
 /*****
diff --git a/src/or/routerlist.c b/src/or/routerlist.c
index f5b216f35f..02564e6662 100644
--- a/src/or/routerlist.c
+++ b/src/or/routerlist.c
@@ -2178,7 +2178,7 @@ scale_array_elements_to_u64(uint64_t *entries_out, const double *entries_in,
   double scale_factor = 0.0;
   int i;
   /* big, but far away from overflowing an int64_t */
-#define SCALE_TO_U64_MAX ((int64_t) (INT64_MAX / 4))
+#define SCALE_TO_U64_MAX ((double) (INT64_MAX / 4))
 
   for (i = 0; i < n_entries; ++i)
     total += entries_in[i];
diff --git a/src/or/scheduler.h b/src/or/scheduler.h
index 94a44a0aa3..3dcfd2faca 100644
--- a/src/or/scheduler.h
+++ b/src/or/scheduler.h
@@ -44,6 +44,13 @@ MOCK_DECL(STATIC int, scheduler_compare_channels,
           (const void *c1_v, const void *c2_v));
 STATIC uint64_t scheduler_get_queue_heuristic(void);
 STATIC void scheduler_update_queue_heuristic(time_t now);
+
+#ifdef TOR_UNIT_TESTS
+extern smartlist_t *channels_pending;
+extern struct event *run_sched_ev;
+extern uint64_t queue_heuristic;
+extern time_t queue_heuristic_timestamp;
+#endif
 #endif
 
 #endif /* !defined(TOR_SCHEDULER_H) */
diff --git a/src/or/tor_main.c b/src/or/tor_main.c
index ac32eef559..21fbe3efb5 100644
--- a/src/or/tor_main.c
+++ b/src/or/tor_main.c
@@ -3,6 +3,8 @@
  * Copyright (c) 2007-2016, The Tor Project, Inc. */
 /* See LICENSE for licensing information */
 
+extern const char tor_git_revision[];
+
 /** String describing which Tor Git repository version the source was
  * built from.  This string is generated by a bit of shell kludging in
  * src/or/include.am, and is usually right.
diff --git a/src/test/bench.c b/src/test/bench.c
index 5aefda5ff2..5595988f31 100644
--- a/src/test/bench.c
+++ b/src/test/bench.c
@@ -3,6 +3,7 @@
  * Copyright (c) 2007-2016, The Tor Project, Inc. */
 /* See LICENSE for licensing information */
 
+extern const char tor_git_revision[];
 /* Ordinarily defined in tor_main.c; this bit is just here to provide one
  * since we're not linking to tor_main.c */
 const char tor_git_revision[] = "";
diff --git a/src/test/example_extrainfo.inc b/src/test/example_extrainfo.inc
index e096afd6c4..0bf2341ef5 100644
--- a/src/test/example_extrainfo.inc
+++ b/src/test/example_extrainfo.inc
@@ -133,7 +133,7 @@ static const char EX_EI_BAD_NICKNAME_KEY[] =
   "/UBWNSyXCFDMqnddb/LZ8+VgttmxfYkpeRzSSmDijN3RbOvYJhhBAgMBAAE=\n"
   "-----END RSA PUBLIC KEY-----\n";
 
-const char EX_EI_BAD_TOKENS[] =
+static const char EX_EI_BAD_TOKENS[] =
   "extra-info bob 6F314FB01A31162BD5E473D4977AC570DC5B86BB\n"
   "published 2014-10-05 20:07:00\n"
   "published 2014-10-05 20:07:00\n"
@@ -145,8 +145,9 @@ const char EX_EI_BAD_TOKENS[] =
   "-----END SIGNATURE-----\n"
   ;
 
-const char EX_EI_BAD_TOKENS_FP[] = "6F314FB01A31162BD5E473D4977AC570DC5B86BB";
-const char EX_EI_BAD_TOKENS_KEY[] =
+static const char EX_EI_BAD_TOKENS_FP[] =
+  "6F314FB01A31162BD5E473D4977AC570DC5B86BB";
+static const char EX_EI_BAD_TOKENS_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBAL7Z8tz45Tb4tnEFS2sAyjubBV/giSfZdmXRkDV8Jo4xqWqhWFJn7+zN\n"
   "AXBWBThGeVH2WXrpz5seNJXgZJPxMTMsrnSCGcRXZw0Npti2MkLuQ6+prZa+OPwE\n"
@@ -210,7 +211,8 @@ static const char EX_EI_GOOD_ED_EI[] =
   "\n"
   "\n"
   ;
-const char EX_EI_GOOD_ED_EI_FP[] = "A692FE045C32B5E3A54B52882EF678A9DAC46A73";
+static const char EX_EI_GOOD_ED_EI_FP[] =
+  "A692FE045C32B5E3A54B52882EF678A9DAC46A73";
 static const char EX_EI_GOOD_ED_EI_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBAM3jdYwjwGxDWYj/vyFkQT7RgeCNIn89Ei6D2+L/fdtFnqrMXOreFFHL\n"
@@ -237,7 +239,8 @@ static const char EX_EI_ED_MISSING_SIG[] =
   "\n"
   "\n"
   ;
-const char EX_EI_ED_MISSING_SIG_FP[] = "2A7521497B91A8437021515308A47491164EDBA1";
+static const char EX_EI_ED_MISSING_SIG_FP[] =
+  "2A7521497B91A8437021515308A47491164EDBA1";
 static const char EX_EI_ED_MISSING_SIG_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBAOOB8ccxbtk2dB5FuKFhGndDcO6STNjB6KiG0b9X2QwKrOZMfmXSigto\n"
@@ -260,7 +263,8 @@ static const char EX_EI_ED_MISSING_CERT[] =
   "\n"
   "\n"
   ;
-const char EX_EI_ED_MISSING_CERT_FP[] = "E88E43E86015345A323D93D825C33E4AD1028F65";
+static const char EX_EI_ED_MISSING_CERT_FP[] =
+  "E88E43E86015345A323D93D825C33E4AD1028F65";
 static const char EX_EI_ED_MISSING_CERT_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBALjA/geb0TR9rp/UPvLhABQpB0XUDYuZAnLkrv+i7AAV7FemTDveEGnc\n"
@@ -284,7 +288,8 @@ static const char EX_EI_ED_BAD_CERT1[] =
   "-----END SIGNATURE-----\n"
   "\n"
   ;
-const char EX_EI_ED_BAD_CERT1_FP[] = "F78D8A655607D32281D02144817A4F1D26AE520F";
+static const char EX_EI_ED_BAD_CERT1_FP[] =
+  "F78D8A655607D32281D02144817A4F1D26AE520F";
 static const char EX_EI_ED_BAD_CERT1_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBAMlR46JhxsCmWYtmIB/JjTV2TUYIhJLmHy+X7FfkK3ZVQvvl9/3GSXFL\n"
@@ -309,7 +314,8 @@ static const char EX_EI_ED_BAD_CERT2[] =
   "cVrtU6RVmzldSbyir8V/Z4S/Cm67gYAgjM5gfoFUqDs=\n"
   "-----END SIGNATURE-----\n"
   ;
-const char EX_EI_ED_BAD_CERT2_FP[] = "7C2B42E783C4E0EB0CC3BDB37385D16737BACFBD";
+static const char EX_EI_ED_BAD_CERT2_FP[] =
+  "7C2B42E783C4E0EB0CC3BDB37385D16737BACFBD";
 static const char EX_EI_ED_BAD_CERT2_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBALAM1F/0XJEsbxIQqb3+ObX/yGVnq9of8Q9sLsmxffD6hwVpCqnV3lTg\n"
@@ -335,7 +341,8 @@ static const char EX_EI_ED_BAD_SIG1[] =
   "-----END SIGNATURE-----\n"
   "\n"
   ;
-const char EX_EI_ED_BAD_SIG1_FP[] = "5AC3A538FEEFC6F9FCC5FA0CE64704396C30D62A";
+static const char EX_EI_ED_BAD_SIG1_FP[] =
+  "5AC3A538FEEFC6F9FCC5FA0CE64704396C30D62A";
 static const char EX_EI_ED_BAD_SIG1_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBAMvb6SuoIkPfBkJgQuo5aQDepAs1kEETZ9VXotMlhB0JJikrqBrAAz+7\n"
@@ -361,7 +368,8 @@ static const char EX_EI_ED_BAD_SIG2[] =
   "-----END SIGNATURE-----\n"
   "\n"
   ;
-const char EX_EI_ED_BAD_SIG2_FP[] = "7F1D4DD477E340C6D6B389FAC26EDC746113082F";
+static const char EX_EI_ED_BAD_SIG2_FP[] =
+  "7F1D4DD477E340C6D6B389FAC26EDC746113082F";
 static const char EX_EI_ED_BAD_SIG2_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBALzOyfCEUZnvCyhlyMctPkdXg/XRE3Cr6QgyzdKf5kQbUiu2n0FgSHOX\n"
@@ -388,7 +396,8 @@ static const char EX_EI_ED_MISPLACED_CERT[] =
   "-----END SIGNATURE-----\n"
   "\n"
   ;
-const char EX_EI_ED_MISPLACED_CERT_FP[] = "3B788BD0CE348BC5CED48313307C78175EB6D0F3";
+static const char EX_EI_ED_MISPLACED_CERT_FP[] =
+  "3B788BD0CE348BC5CED48313307C78175EB6D0F3";
 static const char EX_EI_ED_MISPLACED_CERT_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBALTwNqhTprg1oC6bEbDqwIYBoER6prqUXQFbwbFDn+ekXhZj8vltgGwp\n"
@@ -414,7 +423,8 @@ static const char EX_EI_ED_MISPLACED_SIG[] =
   "-----END SIGNATURE-----\n"
   "\n"
   ;
-const char EX_EI_ED_MISPLACED_SIG_FP[] = "384E40A5DEED4AB1D8A74F1FCBDB18B7C24A8284";
+static const char EX_EI_ED_MISPLACED_SIG_FP[] =
+  "384E40A5DEED4AB1D8A74F1FCBDB18B7C24A8284";
 static const char EX_EI_ED_MISPLACED_SIG_KEY[] =
   "-----BEGIN RSA PUBLIC KEY-----\n"
   "MIGJAoGBAK0HgOCG/6433VCrwz/vhk3cKmyOfenCp0GZ4DIUwPWt4DeyP4nTbN6T\n"
diff --git a/src/test/test-memwipe.c b/src/test/test-memwipe.c
index 5e89534db6..c28d5054a2 100644
--- a/src/test/test-memwipe.c
+++ b/src/test/test-memwipe.c
@@ -14,6 +14,7 @@ static unsigned fill_heap_buffer_memwipe(void) __attribute__((noinline));
 static unsigned fill_heap_buffer_nothing(void) __attribute__((noinline));
 static unsigned check_a_buffer(void) __attribute__((noinline));
 
+extern const char *s; /* Make the linkage global */
 const char *s = NULL;
 
 #define BUF_LEN 2048
diff --git a/src/test/test.c b/src/test/test.c
index 1595c8ee4f..c0faec3027 100644
--- a/src/test/test.c
+++ b/src/test/test.c
@@ -1124,62 +1124,6 @@ static struct testcase_t test_array[] = {
   END_OF_TESTCASES
 };
 
-extern struct testcase_t accounting_tests[];
-extern struct testcase_t addr_tests[];
-extern struct testcase_t address_tests[];
-extern struct testcase_t buffer_tests[];
-extern struct testcase_t cell_format_tests[];
-extern struct testcase_t cell_queue_tests[];
-extern struct testcase_t channel_tests[];
-extern struct testcase_t channeltls_tests[];
-extern struct testcase_t checkdir_tests[];
-extern struct testcase_t circuitlist_tests[];
-extern struct testcase_t circuitmux_tests[];
-extern struct testcase_t compat_libevent_tests[];
-extern struct testcase_t config_tests[];
-extern struct testcase_t connection_tests[];
-extern struct testcase_t container_tests[];
-extern struct testcase_t controller_tests[];
-extern struct testcase_t controller_event_tests[];
-extern struct testcase_t crypto_tests[];
-extern struct testcase_t dir_tests[];
-extern struct testcase_t dir_handle_get_tests[];
-extern struct testcase_t entryconn_tests[];
-extern struct testcase_t entrynodes_tests[];
-extern struct testcase_t guardfraction_tests[];
-extern struct testcase_t extorport_tests[];
-extern struct testcase_t hs_tests[];
-extern struct testcase_t introduce_tests[];
-extern struct testcase_t keypin_tests[];
-extern struct testcase_t link_handshake_tests[];
-extern struct testcase_t logging_tests[];
-extern struct testcase_t microdesc_tests[];
-extern struct testcase_t nodelist_tests[];
-extern struct testcase_t oom_tests[];
-extern struct testcase_t options_tests[];
-extern struct testcase_t policy_tests[];
-extern struct testcase_t procmon_tests[];
-extern struct testcase_t pubsub_tests[];
-extern struct testcase_t pt_tests[];
-extern struct testcase_t relay_tests[];
-extern struct testcase_t relaycell_tests[];
-extern struct testcase_t rend_cache_tests[];
-extern struct testcase_t replaycache_tests[];
-extern struct testcase_t router_tests[];
-extern struct testcase_t routerkeys_tests[];
-extern struct testcase_t routerlist_tests[];
-extern struct testcase_t routerset_tests[];
-extern struct testcase_t scheduler_tests[];
-extern struct testcase_t socks_tests[];
-extern struct testcase_t status_tests[];
-extern struct testcase_t thread_tests[];
-extern struct testcase_t tortls_tests[];
-extern struct testcase_t util_tests[];
-extern struct testcase_t util_format_tests[];
-extern struct testcase_t util_process_tests[];
-extern struct testcase_t dns_tests[];
-extern struct testcase_t handle_tests[];
-
 struct testgroup_t testgroups[] = {
   { "", test_array },
   { "accounting/", accounting_tests },
diff --git a/src/test/test.h b/src/test/test.h
index 153b7cae00..747b61d669 100644
--- a/src/test/test.h
+++ b/src/test/test.h
@@ -163,11 +163,86 @@ struct crypto_pk_t *pk_generate(int idx);
 
 #define CALLED(mock_name) US_CONCAT_2_(NS(mock_name), called)
 #define NS_DECL(retval, mock_fn, args) \
+    extern int CALLED(mock_fn);        \
     static retval NS(mock_fn) args; int CALLED(mock_fn) = 0
 #define NS_MOCK(name) MOCK(name, NS(name))
 #define NS_UNMOCK(name) UNMOCK(name)
 
 extern const struct testcase_setup_t passthrough_setup;
 
+extern struct testcase_t accounting_tests[];
+extern struct testcase_t addr_tests[];
+extern struct testcase_t address_tests[];
+extern struct testcase_t buffer_tests[];
+extern struct testcase_t cell_format_tests[];
+extern struct testcase_t cell_queue_tests[];
+extern struct testcase_t channel_tests[];
+extern struct testcase_t channeltls_tests[];
+extern struct testcase_t checkdir_tests[];
+extern struct testcase_t circuitlist_tests[];
+extern struct testcase_t circuitmux_tests[];
+extern struct testcase_t compat_libevent_tests[];
+extern struct testcase_t config_tests[];
+extern struct testcase_t connection_tests[];
+extern struct testcase_t container_tests[];
+extern struct testcase_t controller_tests[];
+extern struct testcase_t controller_event_tests[];
+extern struct testcase_t crypto_tests[];
+extern struct testcase_t dir_tests[];
+extern struct testcase_t dir_handle_get_tests[];
+extern struct testcase_t entryconn_tests[];
+extern struct testcase_t entrynodes_tests[];
+extern struct testcase_t guardfraction_tests[];
+extern struct testcase_t extorport_tests[];
+extern struct testcase_t hs_tests[];
+extern struct testcase_t introduce_tests[];
+extern struct testcase_t keypin_tests[];
+extern struct testcase_t link_handshake_tests[];
+extern struct testcase_t logging_tests[];
+extern struct testcase_t microdesc_tests[];
+extern struct testcase_t nodelist_tests[];
+extern struct testcase_t oom_tests[];
+extern struct testcase_t options_tests[];
+extern struct testcase_t policy_tests[];
+extern struct testcase_t procmon_tests[];
+extern struct testcase_t pubsub_tests[];
+extern struct testcase_t pt_tests[];
+extern struct testcase_t relay_tests[];
+extern struct testcase_t relaycell_tests[];
+extern struct testcase_t rend_cache_tests[];
+extern struct testcase_t replaycache_tests[];
+extern struct testcase_t router_tests[];
+extern struct testcase_t routerkeys_tests[];
+extern struct testcase_t routerlist_tests[];
+extern struct testcase_t routerset_tests[];
+extern struct testcase_t scheduler_tests[];
+extern struct testcase_t socks_tests[];
+extern struct testcase_t status_tests[];
+extern struct testcase_t thread_tests[];
+extern struct testcase_t tortls_tests[];
+extern struct testcase_t util_tests[];
+extern struct testcase_t util_format_tests[];
+extern struct testcase_t util_process_tests[];
+extern struct testcase_t dns_tests[];
+extern struct testcase_t handle_tests[];
+
+extern struct testcase_t slow_crypto_tests[];
+extern struct testcase_t slow_util_tests[];
+
+extern struct testgroup_t testgroups[];
+
+extern const char AUTHORITY_CERT_1[];
+extern const char AUTHORITY_SIGNKEY_1[];
+extern const char AUTHORITY_SIGNKEY_A_DIGEST[];
+extern const char AUTHORITY_SIGNKEY_A_DIGEST256[];
+extern const char AUTHORITY_CERT_2[];
+extern const char AUTHORITY_SIGNKEY_2[];
+extern const char AUTHORITY_SIGNKEY_B_DIGEST[];
+extern const char AUTHORITY_SIGNKEY_B_DIGEST256[];
+extern const char AUTHORITY_CERT_3[];
+extern const char AUTHORITY_SIGNKEY_3[];
+extern const char AUTHORITY_SIGNKEY_C_DIGEST[];
+extern const char AUTHORITY_SIGNKEY_C_DIGEST256[];
+
 #endif
 
diff --git a/src/test/test_bt_cl.c b/src/test/test_bt_cl.c
index 2f5e50fbf5..95b4f48f11 100644
--- a/src/test/test_bt_cl.c
+++ b/src/test/test_bt_cl.c
@@ -28,6 +28,9 @@ int a_tangled_web(int x) NOINLINE;
 int we_weave(int x) NOINLINE;
 static void abort_handler(int s) NORETURN;
 
+#ifdef HAVE_CFLAG_WNULL_DEREFERENCE
+DISABLE_GCC_WARNING(null-dereference)
+#endif
 int
 crash(int x)
 {
@@ -47,6 +50,9 @@ crash(int x)
   crashtype *= x;
   return crashtype;
 }
+#ifdef HAVE_CFLAG_WNULL_DEREFERENCE
+ENABLE_GCC_WARNING(null-dereference)
+#endif
 
 int
 oh_what(int x)
diff --git a/src/test/test_buffers.c b/src/test/test_buffers.c
index e5e56edf75..95584d54a8 100644
--- a/src/test/test_buffers.c
+++ b/src/test/test_buffers.c
@@ -695,9 +695,9 @@ test_buffers_zlib_fin_at_chunk_end(void *arg)
   tor_free(msg);
 }
 
-const uint8_t *tls_read_ptr;
-int n_remaining;
-int next_reply_val[16];
+static const uint8_t *tls_read_ptr;
+static int n_remaining;
+static int next_reply_val[16];
 
 static int
 mock_tls_read(tor_tls_t *tls, char *cp, size_t len)
diff --git a/src/test/test_channel.c b/src/test/test_channel.c
index 846e419fea..a9e0634d9e 100644
--- a/src/test/test_channel.c
+++ b/src/test/test_channel.c
@@ -20,9 +20,6 @@
 #include "test.h"
 #include "fakechans.h"
 
-/* This comes from channel.c */
-extern uint64_t estimated_total_queue_size;
-
 static int test_chan_accept_cells = 0;
 static int test_chan_fixed_cells_recved = 0;
 static cell_t * test_chan_last_seen_fixed_cell_ptr = NULL;
@@ -33,7 +30,7 @@ static int test_destroy_not_pending_calls = 0;
 static int test_doesnt_want_writes_count = 0;
 static int test_dumpstats_calls = 0;
 static int test_has_waiting_cells_count = 0;
-static double test_overhead_estimate = 1.0f;
+static double test_overhead_estimate = 1.0;
 static int test_releases_count = 0;
 static circuitmux_t *test_target_cmux = NULL;
 static unsigned int test_cmux_cells = 0;
@@ -792,7 +789,7 @@ test_channel_incoming(void *arg)
   /* Accept cells to lower layer */
   test_chan_accept_cells = 1;
   /* Use default overhead factor */
-  test_overhead_estimate = 1.0f;
+  test_overhead_estimate = 1.0;
 
   ch = new_fake_channel();
   tt_assert(ch);
@@ -881,7 +878,7 @@ test_channel_lifecycle(void *arg)
   /* Accept cells to lower layer */
   test_chan_accept_cells = 1;
   /* Use default overhead factor */
-  test_overhead_estimate = 1.0f;
+  test_overhead_estimate = 1.0;
 
   ch1 = new_fake_channel();
   tt_assert(ch1);
@@ -989,7 +986,7 @@ test_channel_lifecycle_2(void *arg)
   /* Accept cells to lower layer */
   test_chan_accept_cells = 1;
   /* Use default overhead factor */
-  test_overhead_estimate = 1.0f;
+  test_overhead_estimate = 1.0;
 
   ch = new_fake_channel();
   tt_assert(ch);
@@ -1136,7 +1133,7 @@ test_channel_multi(void *arg)
   /* Accept cells to lower layer */
   test_chan_accept_cells = 1;
   /* Use default overhead factor */
-  test_overhead_estimate = 1.0f;
+  test_overhead_estimate = 1.0;
 
   ch1 = new_fake_channel();
   tt_assert(ch1);
@@ -1444,7 +1441,7 @@ test_channel_queue_incoming(void *arg)
   /* Accept cells to lower layer */
   test_chan_accept_cells = 1;
   /* Use default overhead factor */
-  test_overhead_estimate = 1.0f;
+  test_overhead_estimate = 1.0;
 
   ch = new_fake_channel();
   tt_assert(ch);
@@ -1584,16 +1581,16 @@ test_channel_queue_size(void *arg)
   /* One cell, times an overhead factor of 1.0 */
   tt_u64_op(ch->bytes_queued_for_xmit, ==, 512);
   /* Try a different overhead factor */
-  test_overhead_estimate = 0.5f;
+  test_overhead_estimate = 0.5;
   /* This one should be ignored since it's below 1.0 */
   channel_update_xmit_queue_size(ch);
   tt_u64_op(ch->bytes_queued_for_xmit, ==, 512);
   /* Now try a larger one */
-  test_overhead_estimate = 2.0f;
+  test_overhead_estimate = 2.0;
   channel_update_xmit_queue_size(ch);
   tt_u64_op(ch->bytes_queued_for_xmit, ==, 1024);
   /* Go back to 1.0 */
-  test_overhead_estimate = 1.0f;
+  test_overhead_estimate = 1.0;
   channel_update_xmit_queue_size(ch);
   tt_u64_op(ch->bytes_queued_for_xmit, ==, 512);
   /* Check the global estimate too */
diff --git a/src/test/test_channeltls.c b/src/test/test_channeltls.c
index 04ae9a6da7..394612f155 100644
--- a/src/test/test_channeltls.c
+++ b/src/test/test_channeltls.c
@@ -185,7 +185,7 @@ test_channeltls_overhead_estimate(void *arg)
   const char test_digest[DIGEST_LEN] = {
     0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a,
     0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14 };
-  float r;
+  double r;
   channel_tls_t *tlschan = NULL;
 
   (void)arg;
@@ -206,31 +206,31 @@ test_channeltls_overhead_estimate(void *arg)
   ch = channel_tls_connect(&test_addr, 567, test_digest);
   tt_assert(ch != NULL);
 
-  /* First case: silly low ratios should get clamped to 1.0f */
+  /* First case: silly low ratios should get clamped to 1.0 */
   tlschan = BASE_CHAN_TO_TLS(ch);
   tt_assert(tlschan != NULL);
   tlschan->conn->bytes_xmitted = 128;
   tlschan->conn->bytes_xmitted_by_tls = 64;
   r = ch->get_overhead_estimate(ch);
-  tt_assert(fabsf(r - 1.0f) < 1E-12);
+  tt_assert(fabs(r - 1.0) < 1E-12);
 
   tlschan->conn->bytes_xmitted_by_tls = 127;
   r = ch->get_overhead_estimate(ch);
-  tt_assert(fabsf(r - 1.0f) < 1E-12);
+  tt_assert(fabs(r - 1.0) < 1E-12);
 
   /* Now middle of the range */
   tlschan->conn->bytes_xmitted_by_tls = 192;
   r = ch->get_overhead_estimate(ch);
-  tt_assert(fabsf(r - 1.5f) < 1E-12);
+  tt_assert(fabs(r - 1.5) < 1E-12);
 
-  /* Now above the 2.0f clamp */
+  /* Now above the 2.0 clamp */
   tlschan->conn->bytes_xmitted_by_tls = 257;
   r = ch->get_overhead_estimate(ch);
-  tt_assert(fabsf(r - 2.0f) < 1E-12);
+  tt_assert(fabs(r - 2.0) < 1E-12);
 
   tlschan->conn->bytes_xmitted_by_tls = 512;
   r = ch->get_overhead_estimate(ch);
-  tt_assert(fabsf(r - 2.0f) < 1E-12);
+  tt_assert(fabs(r - 2.0) < 1E-12);
 
  done:
   if (ch) {
diff --git a/src/test/test_crypto.c b/src/test/test_crypto.c
index 616b313b16..bf4b68efe2 100644
--- a/src/test/test_crypto.c
+++ b/src/test/test_crypto.c
@@ -18,10 +18,6 @@
 #include <openssl/evp.h>
 #include <openssl/rand.h>
 
-extern const char AUTHORITY_SIGNKEY_3[];
-extern const char AUTHORITY_SIGNKEY_A_DIGEST[];
-extern const char AUTHORITY_SIGNKEY_A_DIGEST256[];
-
 /** Run unit tests for Diffie-Hellman functionality. */
 static void
 test_crypto_dh(void *arg)
@@ -277,9 +273,6 @@ test_crypto_rng_range(void *arg)
   ;
 }
 
-extern int break_strongest_rng_fallback;
-extern int break_strongest_rng_syscall;
-
 static void
 test_crypto_rng_strongest(void *arg)
 {
diff --git a/src/test/test_data.c b/src/test/test_data.c
index 32de54bc84..788489a097 100644
--- a/src/test/test_data.c
+++ b/src/test/test_data.c
@@ -3,6 +3,8 @@
  * Copyright (c) 2007-2016, The Tor Project, Inc. */
 /* See LICENSE for licensing information */
 
+#include "test.h"
+
 /* Our unit test expect that the AUTHORITY_CERT_* public keys will sort
  * in this order. */
 #define AUTHORITY_CERT_A AUTHORITY_CERT_3
diff --git a/src/test/test_dir_common.c b/src/test/test_dir_common.c
index 0b446c2dfd..2448d307b2 100644
--- a/src/test/test_dir_common.c
+++ b/src/test/test_dir_common.c
@@ -21,13 +21,6 @@ networkstatus_t * dir_common_add_rs_and_parse(networkstatus_t *vote,
                             crypto_pk_t *sign_skey, int *n_vrs,
                             time_t now, int clear_rl);
 
-extern const char AUTHORITY_CERT_1[];
-extern const char AUTHORITY_SIGNKEY_1[];
-extern const char AUTHORITY_CERT_2[];
-extern const char AUTHORITY_SIGNKEY_2[];
-extern const char AUTHORITY_CERT_3[];
-extern const char AUTHORITY_SIGNKEY_3[];
-
 /** Initialize and set auth certs and keys
  * Returns 0 on success, -1 on failure. Clean up handled by caller.
  */
diff --git a/src/test/test_dir_handle_get.c b/src/test/test_dir_handle_get.c
index 7f92c8c9ed..927fa8b61d 100644
--- a/src/test/test_dir_handle_get.c
+++ b/src/test/test_dir_handle_get.c
@@ -38,7 +38,15 @@
 #include <dirent.h>
 #endif
 
+#ifdef HAVE_CFLAG_WOVERLENGTH_STRINGS
+DISABLE_GCC_WARNING(overlength-strings)
+/* We allow huge string constants in the unit tests, but not in the code
+ * at large. */
+#endif
 #include "vote_descriptors.inc"
+#ifdef HAVE_CFLAG_WOVERLENGTH_STRINGS
+ENABLE_GCC_WARNING(overlength-strings)
+#endif
 
 #define NS_MODULE dir_handle_get
 
@@ -1162,8 +1170,6 @@ test_dir_handle_get_server_keys_all_not_found(void* data)
 
 #define TEST_CERTIFICATE AUTHORITY_CERT_3
 #define TEST_SIGNING_KEY AUTHORITY_SIGNKEY_A_DIGEST
-extern const char AUTHORITY_CERT_3[];
-extern const char AUTHORITY_SIGNKEY_A_DIGEST[];
 
 static const char TEST_CERT_IDENT_KEY[] =
   "D867ACF56A9D229B35C25F0090BC9867E906BE69";
diff --git a/src/test/test_handles.c b/src/test/test_handles.c
index 8aaae13845..536a478689 100644
--- a/src/test/test_handles.c
+++ b/src/test/test_handles.c
@@ -12,8 +12,8 @@ typedef struct demo_t {
   int val;
 } demo_t;
 
-HANDLE_DECL(demo, demo_t, static);
-HANDLE_IMPL(demo, demo_t, static);
+HANDLE_DECL(demo, demo_t, static)
+HANDLE_IMPL(demo, demo_t, static)
 
 static demo_t *
 demo_new(int val)
diff --git a/src/test/test_helpers.c b/src/test/test_helpers.c
index c6daaf220a..ae9fc7a243 100644
--- a/src/test/test_helpers.c
+++ b/src/test/test_helpers.c
@@ -16,7 +16,15 @@
 #include "test.h"
 #include "test_helpers.h"
 
+#ifdef HAVE_CFLAG_WOVERLENGTH_STRINGS
+DISABLE_GCC_WARNING(overlength-strings)
+/* We allow huge string constants in the unit tests, but not in the code
+ * at large. */
+#endif
 #include "test_descriptors.inc"
+#ifdef HAVE_CFLAG_WOVERLENGTH_STRINGS
+ENABLE_GCC_WARNING(overlength-strings)
+#endif
 
 /* Return a statically allocated string representing yesterday's date
  * in ISO format. We use it so that state file items are not found to
diff --git a/src/test/test_introduce.c b/src/test/test_introduce.c
index 9c7a86da66..810b03c93d 100644
--- a/src/test/test_introduce.c
+++ b/src/test/test_introduce.c
@@ -9,8 +9,6 @@
 #define RENDSERVICE_PRIVATE
 #include "rendservice.h"
 
-extern const char AUTHORITY_SIGNKEY_1[];
-
 static uint8_t v0_test_plaintext[] =
     /* 20 bytes of rendezvous point nickname */
   { 0x4e, 0x69, 0x63, 0x6b, 0x6e, 0x61, 0x6d, 0x65,
diff --git a/src/test/test_link_handshake.c b/src/test/test_link_handshake.c
index e8856c60de..4038783459 100644
--- a/src/test/test_link_handshake.c
+++ b/src/test/test_link_handshake.c
@@ -16,7 +16,7 @@
 
 #include "test.h"
 
-var_cell_t *mock_got_var_cell = NULL;
+static var_cell_t *mock_got_var_cell = NULL;
 
 static void
 mock_write_var_cell(const var_cell_t *vc, or_connection_t *conn)
diff --git a/src/test/test_microdesc.c b/src/test/test_microdesc.c
index 581f58b45f..91884e692e 100644
--- a/src/test/test_microdesc.c
+++ b/src/test/test_microdesc.c
@@ -490,6 +490,11 @@ test_md_generate(void *arg)
   routerinfo_free(ri);
 }
 
+#ifdef HAVE_CFLAG_WOVERLENGTH_STRINGS
+DISABLE_GCC_WARNING(overlength-strings)
+/* We allow huge string constants in the unit tests, but not in the code
+ * at large. */
+#endif
 /* Taken at random from my ~/.tor/cached-microdescs file and then
  * hand-munged */
 static const char MD_PARSE_TEST_DATA[] =
@@ -645,6 +650,9 @@ static const char MD_PARSE_TEST_DATA[] =
   "id rsa1024 2A8wYpHxnkKJ92orocvIQBzeHlE\n"
   "p6 allow 80\n"
   ;
+#ifdef HAVE_CFLAG_WOVERLENGTH_STRINGS
+ENABLE_GCC_WARNING(overlength-strings)
+#endif
 
 /** More tests for parsing different kinds of microdescriptors, and getting
  * invalid digests trackd from them. */
diff --git a/src/test/test_options.c b/src/test/test_options.c
index 20e8dd563a..8d1d6f901e 100644
--- a/src/test/test_options.c
+++ b/src/test/test_options.c
@@ -12,7 +12,7 @@
 
 #define ROUTERSET_PRIVATE
 #include "routerset.h"
-
+#include "main.h"
 #include "log_test_helpers.h"
 
 #include "sandbox.h"
@@ -572,8 +572,6 @@ test_options_validate__contactinfo(void *ignored)
   tor_free(msg);
 }
 
-extern int quiet_level;
-
 static void
 test_options_validate__logs(void *ignored)
 {
diff --git a/src/test/test_policy.c b/src/test/test_policy.c
index a939ebf54f..913a2f303a 100644
--- a/src/test/test_policy.c
+++ b/src/test/test_policy.c
@@ -778,8 +778,8 @@ test_policies_reject_port_address(void *arg)
   UNMOCK(get_configured_ports);
 }
 
-smartlist_t *mock_ipv4_addrs = NULL;
-smartlist_t *mock_ipv6_addrs = NULL;
+static smartlist_t *mock_ipv4_addrs = NULL;
+static smartlist_t *mock_ipv6_addrs = NULL;
 
 /* mock get_interface_address6_list, returning a deep copy of the template
  * address list ipv4_interface_address_list or ipv6_interface_address_list */
diff --git a/src/test/test_relaycell.c b/src/test/test_relaycell.c
index 1cd9ff064b..fb6748965a 100644
--- a/src/test/test_relaycell.c
+++ b/src/test/test_relaycell.c
@@ -95,7 +95,7 @@ test_relaycell_resolved(void *arg)
     tt_int_op(srm_ncalls, OP_EQ, 1);                                 \
     tt_ptr_op(srm_conn, OP_EQ, entryconn);                           \
     tt_int_op(srm_atype, OP_EQ, (atype));                            \
-    if (answer) {                                                 \
+    if ((answer) != NULL) {                                          \
       tt_int_op(srm_alen, OP_EQ, sizeof(answer)-1);                  \
       tt_int_op(srm_alen, OP_LT, 512);                                \
       tt_int_op(srm_answer_is_set, OP_EQ, 1);                        \
diff --git a/src/test/test_rendcache.c b/src/test/test_rendcache.c
index d1b52649b2..eac41ecdda 100644
--- a/src/test/test_rendcache.c
+++ b/src/test/test_rendcache.c
@@ -20,11 +20,6 @@ static const int TIME_IN_THE_PAST = -(REND_CACHE_MAX_AGE + \
                                       REND_CACHE_MAX_SKEW + 10);
 static const int TIME_IN_THE_FUTURE = REND_CACHE_MAX_SKEW + 10;
 
-extern strmap_t *rend_cache;
-extern digestmap_t *rend_cache_v2_dir;
-extern strmap_t *rend_cache_failure;
-extern size_t rend_cache_total_allocation;
-
 static rend_data_t *
 mock_rend_data(const char *onion_address)
 {
diff --git a/src/test/test_routerlist.c b/src/test/test_routerlist.c
index 2cffa6e801..34b70ac8a8 100644
--- a/src/test/test_routerlist.c
+++ b/src/test/test_routerlist.c
@@ -24,13 +24,6 @@
 #include "test.h"
 #include "test_dir_common.h"
 
-extern const char AUTHORITY_CERT_1[];
-extern const char AUTHORITY_SIGNKEY_1[];
-extern const char AUTHORITY_CERT_2[];
-extern const char AUTHORITY_SIGNKEY_2[];
-extern const char AUTHORITY_CERT_3[];
-extern const char AUTHORITY_SIGNKEY_3[];
-
 void construct_consensus(char **consensus_text_md);
 
 /* 4 digests + 3 sep + pre + post + NULL */
@@ -423,7 +416,7 @@ test_router_pick_directory_server_impl(void *arg)
   networkstatus_vote_free(con_md);
 }
 
-connection_t *mocked_connection = NULL;
+static connection_t *mocked_connection = NULL;
 
 /* Mock connection_get_by_type_addr_port_purpose by returning
  * mocked_connection. */
diff --git a/src/test/test_routerset.c b/src/test/test_routerset.c
index 74b39c0486..1b526d430b 100644
--- a/src/test/test_routerset.c
+++ b/src/test/test_routerset.c
@@ -432,7 +432,7 @@ NS(test_main)(void *arg)
 NS_DECL(addr_policy_t *, router_parse_addr_policy_item_from_string,
     (const char *s, int assume_action, int *malformed_list));
 
-addr_policy_t *NS(mock_addr_policy);
+static addr_policy_t *NS(mock_addr_policy);
 
 static void
 NS(test_main)(void *arg)
@@ -480,7 +480,7 @@ NS(router_parse_addr_policy_item_from_string)(const char *s,
 NS_DECL(addr_policy_t *, router_parse_addr_policy_item_from_string,
         (const char *s, int assume_action, int *bogus));
 
-addr_policy_t *NS(mock_addr_policy);
+static addr_policy_t *NS(mock_addr_policy);
 
 static void
 NS(test_main)(void *arg)
@@ -527,7 +527,7 @@ NS(router_parse_addr_policy_item_from_string)(const char *s, int assume_action,
 NS_DECL(addr_policy_t *, router_parse_addr_policy_item_from_string,
         (const char *s, int assume_action, int *bad));
 
-addr_policy_t *NS(mock_addr_policy);
+static addr_policy_t *NS(mock_addr_policy);
 
 static void
 NS(test_main)(void *arg)
@@ -1477,7 +1477,7 @@ NS(test_main)(void *arg)
  * routerset or routerinfo.
  */
 
-node_t NS(mock_node);
+static node_t NS(mock_node);
 
 static void
 NS(test_main)(void *arg)
@@ -1504,7 +1504,7 @@ NS(test_main)(void *arg)
  * routerset and no routerinfo.
  */
 
-node_t NS(mock_node);
+static node_t NS(mock_node);
 
 static void
 NS(test_main)(void *arg)
@@ -1603,7 +1603,7 @@ NS(test_main)(void *arg)
 
 NS_DECL(const node_t *, node_get_by_nickname,
     (const char *nickname, int warn_if_unused));
-const char *NS(mock_nickname);
+static const char *NS(mock_nickname);
 
 static void
 NS(test_main)(void *arg)
@@ -1652,8 +1652,8 @@ NS(node_get_by_nickname)(const char *nickname, int warn_if_unused)
 
 NS_DECL(const node_t *, node_get_by_nickname,
     (const char *nickname, int warn_if_unused));
-const char *NS(mock_nickname);
-node_t NS(mock_node);
+static const char *NS(mock_nickname);
+static node_t NS(mock_node);
 
 static void
 NS(test_main)(void *arg)
@@ -1702,8 +1702,8 @@ NS(node_get_by_nickname)(const char *nickname, int warn_if_unused)
 
 NS_DECL(const node_t *, node_get_by_nickname,
     (const char *nickname, int warn_if_unused));
-char *NS(mock_nickname);
-node_t NS(mock_node);
+static char *NS(mock_nickname);
+static node_t NS(mock_node);
 
 static void
 NS(test_main)(void *arg)
@@ -1754,7 +1754,7 @@ NS(node_get_by_nickname)(const char *nickname, int warn_if_unused)
 
 NS_DECL(smartlist_t *, nodelist_get_list, (void));
 
-smartlist_t *NS(mock_smartlist);
+static smartlist_t *NS(mock_smartlist);
 
 static void
 NS(test_main)(void *arg)
@@ -1800,8 +1800,8 @@ NS(nodelist_get_list)(void)
 
 NS_DECL(smartlist_t *, nodelist_get_list, (void));
 
-smartlist_t *NS(mock_smartlist);
-node_t NS(mock_node);
+static smartlist_t *NS(mock_smartlist);
+static node_t NS(mock_node);
 
 static void
 NS(test_main)(void *arg)
diff --git a/src/test/test_scheduler.c b/src/test/test_scheduler.c
index 6e9889b48b..15fbb2d186 100644
--- a/src/test/test_scheduler.c
+++ b/src/test/test_scheduler.c
@@ -24,12 +24,6 @@
 #include "test.h"
 #include "fakechans.h"
 
-/* Statics in scheduler.c exposed to the test suite */
-extern smartlist_t *channels_pending;
-extern struct event *run_sched_ev;
-extern uint64_t queue_heuristic;
-extern time_t queue_heuristic_timestamp;
-
 /* Event base for scheduelr tests */
 static struct event_base *mock_event_base = NULL;
 
diff --git a/src/test/test_slow.c b/src/test/test_slow.c
index c1d2e81914..7c9f0b1cc2 100644
--- a/src/test/test_slow.c
+++ b/src/test/test_slow.c
@@ -18,9 +18,6 @@
 #include "or.h"
 #include "test.h"
 
-extern struct testcase_t slow_crypto_tests[];
-extern struct testcase_t slow_util_tests[];
-
 struct testgroup_t testgroups[] = {
   { "slow/crypto/", slow_crypto_tests },
   { "slow/util/", slow_util_tests },
diff --git a/src/test/test_socks.c b/src/test/test_socks.c
index 6da09fd653..62ff12fe15 100644
--- a/src/test/test_socks.c
+++ b/src/test/test_socks.c
@@ -34,7 +34,7 @@ socks_test_cleanup(const struct testcase_t *testcase, void *ptr)
   return 1;
 }
 
-const struct testcase_setup_t socks_setup = {
+static const struct testcase_setup_t socks_setup = {
   socks_test_setup, socks_test_cleanup
 };
 
diff --git a/src/test/test_status.c b/src/test/test_status.c
index 84a0f6c024..b4438aabe9 100644
--- a/src/test/test_status.c
+++ b/src/test/test_status.c
@@ -310,8 +310,6 @@ NS_DECL(void, logv, (int severity, log_domain_mask_t domain,
 NS_DECL(int, server_mode, (const or_options_t *options));
 
 static routerinfo_t *mock_routerinfo;
-extern int onion_handshakes_requested[MAX_ONION_HANDSHAKE_TYPE+1];
-extern int onion_handshakes_assigned[MAX_ONION_HANDSHAKE_TYPE+1];
 
 static void
 NS(test_main)(void *arg)
diff --git a/src/test/test_tortls.c b/src/test/test_tortls.c
index 973e727b46..42b9ef7733 100644
--- a/src/test/test_tortls.c
+++ b/src/test/test_tortls.c
@@ -8,6 +8,7 @@
 #ifdef _WIN32
 #include <winsock2.h>
 #endif
+#include <math.h>
 
 #ifdef __GNUC__
 #define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
@@ -50,9 +51,6 @@
 #include "log_test_helpers.h"
 #define NS_MODULE tortls
 
-extern tor_tls_context_t *server_tls_context;
-extern tor_tls_context_t *client_tls_context;
-
 #if OPENSSL_VERSION_NUMBER >= OPENSSL_V_SERIES(1,1,0) \
     && !defined(LIBRESSL_VERSION_NUMBER)
 #define OPENSSL_OPAQUE
@@ -277,8 +275,6 @@ test_tortls_get_state_description(void *ignored)
   tor_free(tls);
 }
 
-extern int tor_tls_object_ex_data_index;
-
 static void
 test_tortls_get_by_ssl(void *ignored)
 {
@@ -789,8 +785,6 @@ get_cipher_by_id(uint16_t id)
   return NULL;
 }
 
-extern uint16_t v2_cipher_list[];
-
 static void
 test_tortls_classify_client_ciphers(void *ignored)
 {
@@ -1183,9 +1177,6 @@ test_tortls_get_forced_write_size(void *ignored)
   tor_free(tls);
 }
 
-extern uint64_t total_bytes_written_over_tls;
-extern uint64_t total_bytes_written_by_tls;
-
 static void
 test_tortls_get_write_overhead_ratio(void *ignored)
 {
@@ -1194,17 +1185,17 @@ test_tortls_get_write_overhead_ratio(void *ignored)
 
   total_bytes_written_over_tls = 0;
   ret = tls_get_write_overhead_ratio();
-  tt_int_op(ret, OP_EQ, 1.0);
+  tt_double_op(fabs(ret - 1.0), OP_LT, 1E-12);
 
   total_bytes_written_by_tls = 10;
   total_bytes_written_over_tls = 1;
   ret = tls_get_write_overhead_ratio();
-  tt_int_op(ret, OP_EQ, 10.0);
+  tt_double_op(fabs(ret - 10.0), OP_LT, 1E-12);
 
   total_bytes_written_by_tls = 10;
   total_bytes_written_over_tls = 2;
   ret = tls_get_write_overhead_ratio();
-  tt_int_op(ret, OP_EQ, 5.0);
+  tt_double_op(fabs(ret - 5.0), OP_LT, 1E-12);
 
  done:
   (void)0;
diff --git a/src/test/test_util.c b/src/test/test_util.c
index c3c6035ba4..52bc19ad27 100644
--- a/src/test/test_util.c
+++ b/src/test/test_util.c
@@ -30,6 +30,9 @@
 #include <ctype.h>
 #include <float.h>
 
+#define INFINITY_DBL ((double)INFINITY)
+#define NAN_DBL ((double)NAN)
+
 /* XXXX this is a minimal wrapper to make the unit tests compile with the
  * changed tor_timegm interface. */
 static time_t
@@ -1472,24 +1475,24 @@ test_util_strmisc(void *arg)
 
   {
   /* Test parse_double */
-  double d = tor_parse_double("10", 0, UINT64_MAX,&i,NULL);
+  double d = tor_parse_double("10", 0, (double)UINT64_MAX,&i,NULL);
   tt_int_op(1,OP_EQ, i);
   tt_assert(DBL_TO_U64(d) == 10);
-  d = tor_parse_double("0", 0, UINT64_MAX,&i,NULL);
+  d = tor_parse_double("0", 0, (double)UINT64_MAX,&i,NULL);
   tt_int_op(1,OP_EQ, i);
   tt_assert(DBL_TO_U64(d) == 0);
-  d = tor_parse_double(" ", 0, UINT64_MAX,&i,NULL);
+  d = tor_parse_double(" ", 0, (double)UINT64_MAX,&i,NULL);
   tt_int_op(0,OP_EQ, i);
-  d = tor_parse_double(".0a", 0, UINT64_MAX,&i,NULL);
+  d = tor_parse_double(".0a", 0, (double)UINT64_MAX,&i,NULL);
   tt_int_op(0,OP_EQ, i);
-  d = tor_parse_double(".0a", 0, UINT64_MAX,&i,&cp);
+  d = tor_parse_double(".0a", 0, (double)UINT64_MAX,&i,&cp);
   tt_int_op(1,OP_EQ, i);
-  d = tor_parse_double("-.0", 0, UINT64_MAX,&i,NULL);
+  d = tor_parse_double("-.0", 0, (double)UINT64_MAX,&i,NULL);
   tt_int_op(1,OP_EQ, i);
   tt_assert(DBL_TO_U64(d) == 0);
   d = tor_parse_double("-10", -100.0, 100.0,&i,NULL);
   tt_int_op(1,OP_EQ, i);
-  tt_int_op(-10.0,OP_EQ, d);
+  tt_double_op(fabs(d - -10.0),OP_LT, 1E-12);
   }
 
   {
@@ -4392,7 +4395,7 @@ test_util_clamp_double_to_int64(void *arg)
 {
   (void)arg;
 
-  tt_i64_op(INT64_MIN, ==, clamp_double_to_int64(-INFINITY));
+  tt_i64_op(INT64_MIN, ==, clamp_double_to_int64(-INFINITY_DBL));
   tt_i64_op(INT64_MIN, ==,
             clamp_double_to_int64(-1.0 * pow(2.0, 64.0) - 1.0));
   tt_i64_op(INT64_MIN, ==,
@@ -4405,7 +4408,7 @@ test_util_clamp_double_to_int64(void *arg)
   tt_i64_op(0, ==, clamp_double_to_int64(-0.9));
   tt_i64_op(0, ==, clamp_double_to_int64(-0.1));
   tt_i64_op(0, ==, clamp_double_to_int64(0.0));
-  tt_i64_op(0, ==, clamp_double_to_int64(NAN));
+  tt_i64_op(0, ==, clamp_double_to_int64(NAN_DBL));
   tt_i64_op(0, ==, clamp_double_to_int64(0.1));
   tt_i64_op(0, ==, clamp_double_to_int64(0.9));
   tt_i64_op(1, ==, clamp_double_to_int64(1.0));
@@ -4417,7 +4420,7 @@ test_util_clamp_double_to_int64(void *arg)
             clamp_double_to_int64(pow(2.0, 63.0)));
   tt_i64_op(INT64_MAX, ==,
             clamp_double_to_int64(pow(2.0, 64.0)));
-  tt_i64_op(INT64_MAX, ==, clamp_double_to_int64(INFINITY));
+  tt_i64_op(INT64_MAX, ==, clamp_double_to_int64(INFINITY_DBL));
 
  done:
   ;
diff --git a/src/test/testing_common.c b/src/test/testing_common.c
index 39c3d02ab1..ea9366305c 100644
--- a/src/test/testing_common.c
+++ b/src/test/testing_common.c
@@ -3,6 +3,8 @@
  * Copyright (c) 2007-2016, The Tor Project, Inc. */
 /* See LICENSE for licensing information */
 
+extern const char tor_git_revision[];
+
 /* Ordinarily defined in tor_main.c; this bit is just here to provide one
  * since we're not linking to tor_main.c */
 const char tor_git_revision[] = "";
@@ -215,8 +217,6 @@ const struct testcase_setup_t passthrough_setup = {
   passthrough_test_setup, passthrough_test_cleanup
 };
 
-extern struct testgroup_t testgroups[];
-
 /** Main entry point for unit test code: parse the command line, and run
  * some unit tests. */
 int
diff --git a/src/test/vote_descriptors.inc b/src/test/vote_descriptors.inc
index c5ce21f744..895dc6c65c 100644
--- a/src/test/vote_descriptors.inc
+++ b/src/test/vote_descriptors.inc
@@ -1,4 +1,4 @@
-const char* VOTE_BODY_V3 = 
+static const char* VOTE_BODY_V3 =
 "network-status-version 3\n"
 "vote-status vote\n"
 "consensus-methods 13 14 15 16 17 18 19 20 21\n"
diff --git a/src/tools/tor-gencert.c b/src/tools/tor-gencert.c
index c05066722a..7781966024 100644
--- a/src/tools/tor-gencert.c
+++ b/src/tools/tor-gencert.c
@@ -39,21 +39,21 @@
 #define DEFAULT_LIFETIME 12
 
 /* These globals are set via command line options. */
-char *identity_key_file = NULL;
-char *signing_key_file = NULL;
-char *certificate_file = NULL;
-int reuse_signing_key = 0;
-int verbose = 0;
-int make_new_id = 0;
-int months_lifetime = DEFAULT_LIFETIME;
-int passphrase_fd = -1;
-char *address = NULL;
-
-char *passphrase = NULL;
-size_t passphrase_len = 0;
-
-EVP_PKEY *identity_key = NULL;
-EVP_PKEY *signing_key = NULL;
+static char *identity_key_file = NULL;
+static char *signing_key_file = NULL;
+static char *certificate_file = NULL;
+static int reuse_signing_key = 0;
+static int verbose = 0;
+static int make_new_id = 0;
+static int months_lifetime = DEFAULT_LIFETIME;
+static int passphrase_fd = -1;
+static char *address = NULL;
+
+static char *passphrase = NULL;
+static size_t passphrase_len = 0;
+
+static EVP_PKEY *identity_key = NULL;
+static EVP_PKEY *signing_key = NULL;
 
 /** Write a usage message for tor-gencert to stderr. */
 static void