diff --git a/libtransmission/announcer-udp.cc b/libtransmission/announcer-udp.cc
index 46e052e36..83a238a62 100644
--- a/libtransmission/announcer-udp.cc
+++ b/libtransmission/announcer-udp.cc
@@ -144,7 +144,7 @@ struct tau_scrape_request
         }
     }
 
-    [[nodiscard]] auto expiresAt() const noexcept
+    [[nodiscard]] constexpr auto expiresAt() const noexcept
     {
         return created_at_ + TR_SCRAPE_TIMEOUT_SEC.count();
     }
@@ -241,7 +241,7 @@ struct tau_announce_request
         }
     }
 
-    [[nodiscard]] auto expiresAt() const noexcept
+    [[nodiscard]] constexpr auto expiresAt() const noexcept
     {
         return created_at_ + TR_ANNOUNCE_TIMEOUT_SEC.count();
     }
diff --git a/libtransmission/web.cc b/libtransmission/web.cc
index 6cabd31e8..07c06fa8d 100644
--- a/libtransmission/web.cc
+++ b/libtransmission/web.cc
@@ -245,7 +245,7 @@ public:
             easy_dispose(easy_);
         }
 
-        [[nodiscard]] auto* easy() const
+        [[nodiscard]] constexpr auto* easy() const
         {
             return easy_;
         }
@@ -255,42 +255,42 @@ public:
             return options.buffer != nullptr ? options.buffer : privbuf.get();
         }
 
-        [[nodiscard]] auto const& speedLimitTag() const
+        [[nodiscard]] constexpr auto const& speedLimitTag() const
         {
             return options.speed_limit_tag;
         }
 
-        [[nodiscard]] auto const& url() const
+        [[nodiscard]] constexpr auto const& url() const
         {
             return options.url;
         }
 
-        [[nodiscard]] auto const& range() const
+        [[nodiscard]] constexpr auto const& range() const
         {
             return options.range;
         }
 
-        [[nodiscard]] auto const& cookies() const
+        [[nodiscard]] constexpr auto const& cookies() const
         {
             return options.cookies;
         }
 
-        [[nodiscard]] auto const& sndbuf() const
+        [[nodiscard]] constexpr auto const& sndbuf() const
         {
             return options.sndbuf;
         }
 
-        [[nodiscard]] auto const& rcvbuf() const
+        [[nodiscard]] constexpr auto const& rcvbuf() const
         {
             return options.rcvbuf;
         }
 
-        [[nodiscard]] auto const& timeoutSecs() const
+        [[nodiscard]] constexpr auto const& timeoutSecs() const
         {
             return options.timeout_secs;
         }
 
-        [[nodiscard]] auto ipProtocol() const
+        [[nodiscard]] constexpr auto ipProtocol() const
         {
             switch (options.ip_proto)
             {
diff --git a/libtransmission/webseed.cc b/libtransmission/webseed.cc
index 1a33730da..a844badb2 100644
--- a/libtransmission/webseed.cc
+++ b/libtransmission/webseed.cc
@@ -215,7 +215,7 @@ public:
         return bandwidth_;
     }
 
-    [[nodiscard]] size_t activeReqCount(tr_direction dir) const noexcept override
+    [[nodiscard]] TR_CONSTEXPR20 size_t activeReqCount(tr_direction dir) const noexcept override
     {
         if (dir == TR_CLIENT_TO_PEER) // blocks we've requested
         {