diff --git a/cpp/ql/test/query-tests/Security/CWE/CWE-457/semmle/tests/too_many_constants.cpp b/cpp/ql/test/query-tests/Security/CWE/CWE-457/semmle/tests/too_many_constants.cpp
new file mode 100644
index 000000000000..2e794f387ce8
--- /dev/null
+++ b/cpp/ql/test/query-tests/Security/CWE/CWE-457/semmle/tests/too_many_constants.cpp
@@ -0,0 +1,42 @@
+struct S {
+  int a;
+  int b;
+  int c;
+  unsigned long *d;
+
+  union {
+    struct {
+      const char *e;
+      int f;
+      S *g;
+      const char *h;
+      int i;
+      bool j;
+      bool k;
+      const char *l;
+      char **m;
+    } n;
+
+    struct {
+      bool o;
+      bool p;
+    } q;
+  } r;
+};
+
+int too_many_constants_init(S *s);
+
+char *too_many_constants(const char *h, bool k, int i) {
+  const char *e = "";
+  char l[64] = "";
+  char *m;
+
+  S s[] = {
+      {.a = 0, .c = 0, .d = nullptr, .r = {.n = {.e = e, .f = 1, .g = nullptr, .h = h, .i = i, .j = false, .k = k, .l = l, .m = &m}}},
+      {.a = 0, .c = 0, .d = nullptr, .r = {.q = {.o = true, .p = true}}}
+  };
+
+  too_many_constants_init(s);
+
+  return m; // GOOD - initialized by too_many_constants_init
+}