diff --git a/tests/regression/27-inv_invariants/20-union-map-domain-float-int.c b/tests/regression/27-inv_invariants/20-union-map-domain-float-int.c
new file mode 100644
index 0000000000..40ff1d77da
--- /dev/null
+++ b/tests/regression/27-inv_invariants/20-union-map-domain-float-int.c
@@ -0,0 +1,28 @@
+// PARAM: --enable ana.float.interval --set ana.base.unions.domain map
+#include <goblint.h>
+union u {
+	int x;
+	float f;
+};
+
+int main(){
+	union u a;
+	union u b;
+
+	a.x = 12;
+	b.f = 129.0;
+
+	int i = 0;
+	if(a.x == b.x){
+		i++;
+	}
+	// Should not be dead after if
+	__goblint_check(1);
+
+	if(a.f == b.f){
+		i++;
+	}
+	// Should not be dead after if
+	__goblint_check(1);
+	return 0;
+}