diff --git a/gtk/DetailsDialog.cc b/gtk/DetailsDialog.cc
index 830713901..b2ea56262 100644
--- a/gtk/DetailsDialog.cc
+++ b/gtk/DetailsDialog.cc
@@ -1307,7 +1307,7 @@ void DetailsDialog::Impl::refreshPeerList(std::vector<tr_torrent*> const& torren
     {
         auto const* tor = torrents.at(i);
 
-        for (int j = 0; j < peerCount[i]; ++j)
+        for (size_t j = 0; j < peerCount[i]; ++j)
         {
             auto const* s = &peers.at(i)[j];
             auto const key = make_key(tor, s);
diff --git a/gtk/Session.h b/gtk/Session.h
index 96ecfe1c5..b83fc3d60 100644
--- a/gtk/Session.h
+++ b/gtk/Session.h
@@ -158,7 +158,7 @@ public:
     Gtk::TreeModelColumn<tr_torrent_activity> activity;
     Gtk::TreeModelColumn<bool> finished;
     Gtk::TreeModelColumn<tr_priority_t> priority;
-    Gtk::TreeModelColumn<int> queue_position;
+    Gtk::TreeModelColumn<size_t> queue_position;
     Gtk::TreeModelColumn<unsigned int> trackers;
     /* tr_stat.error
      * Tracked because ACTIVITY_FILTER_ERROR needs the row-changed events */
diff --git a/libtransmission/peer-io.cc b/libtransmission/peer-io.cc
index 3f56c9de2..0b134bb67 100644
--- a/libtransmission/peer-io.cc
+++ b/libtransmission/peer-io.cc
@@ -192,7 +192,7 @@ static void event_read_cb(evutil_socket_t fd, short /*event*/, void* vio)
     io->pendingEvents &= ~EV_READ;
 
     auto const curlen = io->readBufferSize();
-    unsigned int howmuch = static_cast<unsigned int>(curlen >= max ? 0 : max - curlen);
+    auto howmuch = static_cast<unsigned int>(curlen >= max ? 0 : max - curlen);
     howmuch = io->bandwidth().clamp(TR_DOWN, howmuch);
 
     tr_logAddTraceIo(io, "libevent says this peer is ready to read");
diff --git a/libtransmission/peer-mgr.cc b/libtransmission/peer-mgr.cc
index bdde78251..a129cb311 100644
--- a/libtransmission/peer-mgr.cc
+++ b/libtransmission/peer-mgr.cc
@@ -2332,7 +2332,7 @@ auto constexpr MaxUploadIdleSecs = time_t{ 60 * 5 };
     /* disconnect if it's been too long since piece data has been transferred.
      * this is on a sliding scale based on number of available peers... */
     {
-        auto const relax_strictness_if_fewer_than_n = std::lround(getMaxPeerCount(tor) * 0.9);
+        auto const relax_strictness_if_fewer_than_n = static_cast<size_t>(std::lround(getMaxPeerCount(tor) * 0.9));
         /* if we have >= relaxIfFewerThan, strictness is 100%.
          * if we have zero connections, strictness is 0% */
         float const strictness = peer_count >= relax_strictness_if_fewer_than_n ?
diff --git a/libtransmission/rpcimpl.cc b/libtransmission/rpcimpl.cc
index 74f9742d4..7f6b9e972 100644
--- a/libtransmission/rpcimpl.cc
+++ b/libtransmission/rpcimpl.cc
@@ -1063,12 +1063,11 @@ static char const* setFilePriorities(tr_torrent* tor, tr_priority_t priority, tr
     {
         for (size_t i = 0; i < n; ++i)
         {
-            auto tmp = int64_t{};
-            if (tr_variantGetInt(tr_variantListChild(list, i), &tmp))
+            if (auto val = int64_t{}; tr_variantGetInt(tr_variantListChild(list, i), &val))
             {
-                if (0 <= tmp && tmp < n_files)
+                if (auto const file_index = static_cast<tr_file_index_t>(val); file_index < n_files)
                 {
-                    files.push_back(tr_file_index_t(tmp));
+                    files.push_back(file_index);
                 }
                 else
                 {
@@ -1093,7 +1092,7 @@ static char const* setFileDLs(tr_torrent* tor, bool wanted, tr_variant* list)
     char const* errmsg = nullptr;
 
     auto const n_files = tor->fileCount();
-    size_t const n_items = tr_variantListSize(list);
+    auto const n_items = tr_variantListSize(list);
 
     auto files = std::vector<tr_file_index_t>{};
     files.reserve(n_files);
@@ -1102,12 +1101,11 @@ static char const* setFileDLs(tr_torrent* tor, bool wanted, tr_variant* list)
     {
         for (size_t i = 0; i < n_items; ++i)
         {
-            auto file_index = int64_t{};
-            if (tr_variantGetInt(tr_variantListChild(list, i), &file_index))
+            if (auto val = int64_t{}; tr_variantGetInt(tr_variantListChild(list, i), &val))
             {
-                if (0 <= file_index && file_index < n_files)
+                if (auto const file_index = static_cast<tr_file_index_t>(val); file_index < n_files)
                 {
-                    files.push_back(static_cast<tr_file_index_t>(file_index));
+                    files.push_back(file_index);
                 }
                 else
                 {
diff --git a/libtransmission/session.cc b/libtransmission/session.cc
index fef42f41f..e9e9e9a9d 100644
--- a/libtransmission/session.cc
+++ b/libtransmission/session.cc
@@ -2606,7 +2606,7 @@ size_t tr_session::countQueueFreeSlots(tr_direction dir) const noexcept
     auto const activity = dir == TR_UP ? TR_STATUS_SEED : TR_STATUS_DOWNLOAD;
 
     /* count how many torrents are active */
-    int active_count = 0;
+    auto active_count = size_t{};
     bool const stalled_enabled = queueStalledEnabled();
     int const stalled_if_idle_for_n_seconds = queueStalledMinutes() * 60;
     time_t const now = tr_time();
diff --git a/libtransmission/torrent.cc b/libtransmission/torrent.cc
index daf4a9c7a..9c6327c1e 100644
--- a/libtransmission/torrent.cc
+++ b/libtransmission/torrent.cc
@@ -1134,7 +1134,7 @@ tr_stat const* tr_torrentStat(tr_torrent* tor)
             auto seed_idle_minutes = uint16_t{};
             s->etaIdle = tor->etaSpeed_Bps < 1 && tr_torrentGetSeedIdle(tor, &seed_idle_minutes) ?
                 seed_idle_minutes * 60 - s->idleSecs :
-                TR_ETA_NOT_AVAIL;
+                static_cast<time_t>(TR_ETA_NOT_AVAIL);
         }
 
         break;