diff --git a/src/test/excessiveblock_tests.cpp b/src/test/excessiveblock_tests.cpp
--- a/src/test/excessiveblock_tests.cpp
+++ b/src/test/excessiveblock_tests.cpp
@@ -55,8 +55,9 @@
                 std::to_string(std::numeric_limits<int64_t>::max())));
 
     BOOST_CHECK_THROW(
-        CallRPC(std::string("setexcessiveblock ") +
-                std::to_string(std::numeric_limits<int64_t>::max() + 1)),
+        CallRPC(
+            std::string("setexcessiveblock ") +
+            std::to_string(uint64_t(std::numeric_limits<int64_t>::max()) + 1)),
         std::runtime_error);
 
     BOOST_CHECK_THROW(