diff --git a/src/cmd/compile/internal/types2/check_test.go b/src/cmd/compile/internal/types2/check_test.go
index b149ae3908..8cb3000501 100644
--- a/src/cmd/compile/internal/types2/check_test.go
+++ b/src/cmd/compile/internal/types2/check_test.go
@@ -317,7 +317,32 @@ func TestManual(t *testing.T) {
 	}
 }
 
-// TODO(gri) go/types has extra TestLongConstants and TestIndexRepresentability tests
+func TestLongConstants(t *testing.T) {
+	format := `package longconst; const _ = %s /* ERROR "constant overflow" */; const _ = %s // ERROR "excessively long constant"`
+	src := fmt.Sprintf(format, strings.Repeat("1", 9999), strings.Repeat("1", 10001))
+	testFiles(t, []string{"longconst.go"}, [][]byte{[]byte(src)}, 0, false)
+}
+
+func withSizes(sizes Sizes) func(*Config) {
+	return func(cfg *Config) {
+		cfg.Sizes = sizes
+	}
+}
+
+// TestIndexRepresentability tests that constant index operands must
+// be representable as int even if they already have a type that can
+// represent larger values.
+func TestIndexRepresentability(t *testing.T) {
+	const src = `package index; var s []byte; var _ = s[int64 /* ERRORx "int64\\(1\\) << 40 \\(.*\\) overflows int" */ (1) << 40]`
+	testFiles(t, []string{"index.go"}, [][]byte{[]byte(src)}, 0, false, withSizes(&StdSizes{4, 4}))
+}
+
+func TestIssue47243_TypedRHS(t *testing.T) {
+	// The RHS of the shift expression below overflows uint on 32bit platforms,
+	// but this is OK as it is explicitly typed.
+	const src = `package issue47243; var a uint64; var _ = a << uint64(4294967296)` // uint64(1<<32)
+	testFiles(t, []string{"p.go"}, [][]byte{[]byte(src)}, 0, false, withSizes(&StdSizes{4, 4}))
+}
 
 func TestCheck(t *testing.T) {
 	DefPredeclaredTestFuncs()