diff --git a/src/cmd/go/test.go b/src/cmd/go/test.go
index 995ba146f5..e23f939255 100644
--- a/src/cmd/go/test.go
+++ b/src/cmd/go/test.go
@@ -1206,11 +1206,11 @@ func (b *builder) notest(a *action) error {
 	return nil
 }
 
-// isTestMain tells whether fn is a TestMain(m *testing.M) function.
-func isTestMain(fn *ast.FuncDecl) bool {
-	if fn.Name.String() != "TestMain" ||
-		fn.Type.Results != nil && len(fn.Type.Results.List) > 0 ||
-		fn.Type.Params == nil ||
+// isTestFunc tells whether fn has the type of a testing function. arg
+// specifies the parameter type we look for: B, M or T.
+func isTestFunc(fn *ast.FuncDecl, arg string) bool {
+	if fn.Type.Results != nil && len(fn.Type.Results.List) > 0 ||
+		fn.Type.Params.List == nil ||
 		len(fn.Type.Params.List) != 1 ||
 		len(fn.Type.Params.List[0].Names) > 1 {
 		return false
@@ -1222,10 +1222,11 @@ func isTestMain(fn *ast.FuncDecl) bool {
 	// We can't easily check that the type is *testing.M
 	// because we don't know how testing has been imported,
 	// but at least check that it's *M or *something.M.
-	if name, ok := ptr.X.(*ast.Ident); ok && name.Name == "M" {
+	// Same applies for B and T.
+	if name, ok := ptr.X.(*ast.Ident); ok && name.Name == arg {
 		return true
 	}
-	if sel, ok := ptr.X.(*ast.SelectorExpr); ok && sel.Sel.Name == "M" {
+	if sel, ok := ptr.X.(*ast.SelectorExpr); ok && sel.Sel.Name == arg {
 		return true
 	}
 	return false
@@ -1344,16 +1345,22 @@ func (t *testFuncs) load(filename, pkg string, doImport, seen *bool) error {
 		}
 		name := n.Name.String()
 		switch {
-		case isTestMain(n):
+		case name == "TestMain" && isTestFunc(n, "M"):
 			if t.TestMain != nil {
 				return errors.New("multiple definitions of TestMain")
 			}
 			t.TestMain = &testFunc{pkg, name, ""}
 			*doImport, *seen = true, true
 		case isTest(name, "Test"):
+			if !isTestFunc(n, "T") {
+				return fmt.Errorf("wrong type for %s", name)
+			}
 			t.Tests = append(t.Tests, testFunc{pkg, name, ""})
 			*doImport, *seen = true, true
 		case isTest(name, "Benchmark"):
+			if !isTestFunc(n, "B") {
+				return fmt.Errorf("wrong type for %s", name)
+			}
 			t.Benchmarks = append(t.Benchmarks, testFunc{pkg, name, ""})
 			*doImport, *seen = true, true
 		}