diff --git a/src/throw.cpp b/src/throw.cpp
index 63b2e46..74b34e8 100644
--- a/src/throw.cpp
+++ b/src/throw.cpp
@@ -33,7 +33,7 @@ void __throw_if_min1(int x,
     if (x == -1) {
         error_code ec {errno, system_category()};
         ostringstream ec_str;
-        ec_str << "system error " <<  ec.value() << ": " << ec.message();
+        ec_str << "system error " <<  ec.value();
         string msg {combine_message_elements(file, line, message, ec_str.str().c_str())};
         throw system_error {ec, msg};
     }