diff --git a/compiler/test/run.d b/compiler/test/run.d
index 208193cf1dc8..efc5e3d9df27 100755
--- a/compiler/test/run.d
+++ b/compiler/test/run.d
@@ -199,7 +199,7 @@ Options:
             {
                 const string name = target.filename
                             ? target.normalizedTestName
-                            : "`unit` tests: " ~ (cast(string)unitTestRunnerCommand) ~ join(target.args, " ");
+                            : "`unit` tests: " ~ (cast(string)unitTestRunnerCommand) ~ " " ~ join(target.args, " ");
 
                 writeln(">>> TARGET FAILED: ", name);
                 synchronized failedTargets ~= name;