diff --git a/gcc/testsuite/rust/compile/tuple_float_index.rs b/gcc/testsuite/rust/compile/tuple_float_index.rs
new file mode 100644
index 000000000000..87410c5708d7
--- /dev/null
+++ b/gcc/testsuite/rust/compile/tuple_float_index.rs
@@ -0,0 +1,6 @@
+fn main() {
+    let tuple = (((),()),);
+
+    // Do not reformat, the space after the second dot is required
+    let _ = tuple.0. 1;
+}