diff --git a/src/cmd/go/doc.go b/src/cmd/go/doc.go
index 6de4405625..101ecf1c2d 100644
--- a/src/cmd/go/doc.go
+++ b/src/cmd/go/doc.go
@@ -766,6 +766,8 @@ will compile the test binary and then run it as
 The test flags that generate profiles also leave the test binary in pkg.test
 for use when analyzing the profiles.
 
+Flags not recognized by 'go test' must be placed after any specified packages.
+
 
 Description of testing functions
 
diff --git a/src/cmd/go/test.go b/src/cmd/go/test.go
index 48c77fc049..9a8e11d27c 100644
--- a/src/cmd/go/test.go
+++ b/src/cmd/go/test.go
@@ -167,6 +167,8 @@ will compile the test binary and then run it as
 
 The test flags that generate profiles also leave the test binary in pkg.test
 for use when analyzing the profiles.
+
+Flags not recognized by 'go test' must be placed after any specified packages.
 `,
 }