diff --git a/include/nlohmann/detail/input/binary_reader.hpp b/include/nlohmann/detail/input/binary_reader.hpp
index efa93070d..e0343fd0b 100644
--- a/include/nlohmann/detail/input/binary_reader.hpp
+++ b/include/nlohmann/detail/input/binary_reader.hpp
@@ -1434,7 +1434,7 @@ class binary_reader
                 // a copy, not a reference: it must stay valid across the
                 // pop_back() below, which destroys the container_stack element
                 // it would otherwise alias
-                container_frame top = container_stack.back();
+                const container_frame top = container_stack.back();
                 bool at_end = false;
 
                 if (top.remaining != npos)
@@ -2211,7 +2211,7 @@ class binary_reader
             // would otherwise alias.
             for (;;)
             {
-                container_frame top = container_stack.back();
+                const container_frame top = container_stack.back();
 
                 if (top.remaining != npos)
                 {
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
index 150118a1c..3b2233a57 100644
--- a/single_include/nlohmann/json.hpp
+++ b/single_include/nlohmann/json.hpp
@@ -13383,7 +13383,7 @@ class binary_reader
                 // a copy, not a reference: it must stay valid across the
                 // pop_back() below, which destroys the container_stack element
                 // it would otherwise alias
-                container_frame top = container_stack.back();
+                const container_frame top = container_stack.back();
                 bool at_end = false;
 
                 if (top.remaining != npos)
@@ -14160,7 +14160,7 @@ class binary_reader
             // would otherwise alias.
             for (;;)
             {
-                container_frame top = container_stack.back();
+                const container_frame top = container_stack.back();
 
                 if (top.remaining != npos)
                 {
diff --git a/tests/src/unit-serialization.cpp b/tests/src/unit-serialization.cpp
index eddf59f2c..511108c64 100644
--- a/tests/src/unit-serialization.cpp
+++ b/tests/src/unit-serialization.cpp
@@ -469,7 +469,7 @@ TEST_CASE("serialization of strings (bulk fast path)")
     SECTION("invalid UTF-8 handling is unaffected by the fast path")
     {
         const json j = std::string("valid\xff" "more");
-        CHECK_THROWS_WITH_AS(j.dump(), "[json.exception.type_error.316] invalid UTF-8 byte at index 5: 0xFF", json::type_error&);
+        CHECK_THROWS_WITH_AS(utils::ignore_return_value(j.dump()), "[json.exception.type_error.316] invalid UTF-8 byte at index 5: 0xFF", json::type_error&);
         CHECK(j.dump(-1, ' ', false, json::error_handler_t::replace) == "\"valid\xef\xbf\xbd" "more\"");
         CHECK(j.dump(-1, ' ', true, json::error_handler_t::replace) == "\"valid\\ufffdmore\"");
         CHECK(j.dump(-1, ' ', false, json::error_handler_t::ignore) == "\"validmore\"");