diff --git a/test/beast/core/error.cpp b/test/beast/core/error.cpp
index 7b319bdb..1c85edaf 100644
--- a/test/beast/core/error.cpp
+++ b/test/beast/core/error.cpp
@@ -34,14 +34,14 @@ public:
             BEAST_EXPECT(ec.category().name() != nullptr);
             BEAST_EXPECT(! ec.message().empty());
             BEAST_EXPECT(ec == c);
-            BEAST_EXPECT(ec.message(nullptr, 0) != nullptr);
+            BEAST_EXPECT(ec.message() != "");
         }
         {
             auto ec = make_error_condition(c);
             BEAST_EXPECT(ec.category().name() != nullptr);
             BEAST_EXPECT(! ec.message().empty());
             BEAST_EXPECT(ec == c);
-            BEAST_EXPECT(ec.message(nullptr, 0) != nullptr);
+            BEAST_EXPECT(ec.message() != "");
         }
     }
 
diff --git a/test/beast/http/error.cpp b/test/beast/http/error.cpp
index 1ffb4a3c..24dddbbb 100644
--- a/test/beast/http/error.cpp
+++ b/test/beast/http/error.cpp
@@ -38,7 +38,7 @@ public:
         BEAST_EXPECT(cat.equivalent(ec,
             static_cast<std::underlying_type<error>::type>(ev)));
 
-        BEAST_EXPECT(ec.message(nullptr, 0) != nullptr);
+        BEAST_EXPECT(ec.message() != "");
     }
 
     void
diff --git a/test/beast/websocket/error.cpp b/test/beast/websocket/error.cpp
index 0e7e6e2f..dd9a35d8 100644
--- a/test/beast/websocket/error.cpp
+++ b/test/beast/websocket/error.cpp
@@ -36,8 +36,8 @@ public:
         BEAST_EXPECT(! ec.message().empty());
         BEAST_EXPECT(ec == c);
 
-        BEAST_EXPECT(ec.message(nullptr, 0) != nullptr);
-        BEAST_EXPECT(make_error_condition(c).message(nullptr, 0) != nullptr);
+        BEAST_EXPECT(ec.message() != "");
+        BEAST_EXPECT(make_error_condition(c).message() != "");
     }
 
     void run() override
diff --git a/test/beast/zlib/error.cpp b/test/beast/zlib/error.cpp
index 623964c7..bd4a05d5 100644
--- a/test/beast/zlib/error.cpp
+++ b/test/beast/zlib/error.cpp
@@ -37,7 +37,7 @@ public:
         BEAST_EXPECT(cat.equivalent(ec,
             static_cast<std::underlying_type<error>::type>(ev)));
 
-        BEAST_EXPECT(ec.message(nullptr, 0) != nullptr);
+        BEAST_EXPECT(ec.message() != "");
     }
 
     void run() override