--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.target/i386/pr88785.C	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,197 @@
+// PR target/88785
+// { dg-do compile }
+// { dg-options "-O2 -g -std=c++17 -mavx512vl -mavx512dq" }
+
+namespace a {
+template <class> class b;
+template <class> class d;
+}
+template <int f> struct g { static constexpr int e = f; };
+template <typename> struct aa;
+template <typename...> struct o;
+template <typename h, typename ab> struct o<h, ab> : aa<h>::ac {};
+template <typename...> struct j;
+template <typename h, typename ab> struct j<h, ab> : aa<ab>::ac {};
+template <typename... k> constexpr bool l = o<k...>::e;
+template <typename, typename> struct r : g<false> {};
+template <typename m> struct r<m, m> : g<true> {};
+template <typename ad> struct aa { typedef ad ac; };
+template <bool, typename ad, typename> using ae = ad;
+template <typename...> using af = void;
+typedef float ag __attribute__((__vector_size__(16)));
+ag ah;
+ag ai(__attribute__((__vector_size__(2 * sizeof(long long)))) long long z) {
+  ah = ag{};
+  __attribute__((__vector_size__(4 * sizeof(float)))) float aj = ah;
+  return __builtin_ia32_cvtqq2ps128_mask(z, aj, 1);
+}
+namespace a {
+int ak;
+int al;
+template <long> int am;
+template <class> struct an;
+template <class> struct ao;
+template <class m> using ap = typename ao<m>::ac;
+template <class, unsigned long, class = af<>> struct aq;
+template <class m> using ar = aq<m, sizeof(m)>;
+template <class as, class at> as au(at);
+template <class> struct av;
+template <class m> using aw = typename av<m>::ac;
+template <class m, int ax> struct ay {
+  static constexpr long az = ax * sizeof(int);
+  using ac [[gnu::__vector_size__(az)]] = m;
+};
+template <class m, long ba> using bb = typename ay<m, ba>::ac;
+template <class m> struct p {
+  using bc = decltype(m()[0]);
+  static constexpr int bd = sizeof(bc);
+};
+template <class as, class m, class = p<m>> as be(m);
+template <class as, class... at> as bf(at... z) { return be<as>(z...); }
+template <class m, unsigned long ax, class bg = aw<m>> bg bh(aq<m, ax>) {
+  return bg();
+}
+template <> struct av<float> {
+  using ac [[gnu::__vector_size__(16)]] = float;
+};
+template <class> struct av {
+  using ac [[gnu::__vector_size__(16)]] = long long;
+};
+template <unsigned long bi> struct aq<bool, bi> {};
+template <class m, unsigned long bi, class bj = bb<m, bi>,
+          bool = l<r<bb<m, bi>, aw<m>>, r<bj, m>>>
+struct bk;
+template <class m, unsigned long bi, class bj> struct bk<m, bi, bj, true> {
+  bj bl;
+  bk(bb<m, bi> z) : bl(z) {}
+};
+template <class m, unsigned long bi, class bj> struct bk<m, bi, bj, false> {};
+template <class m, unsigned long bi> struct aq<m, bi> : bk<m, bi> {
+  using bm = bb<m, bi>;
+  static constexpr long bd = bi;
+  aq();
+  template <class bn> aq(bn z) : bk<m, bi>(z) {}
+  m operator[](long);
+};
+template <class> constexpr long bo = g<0>::e;
+template <class m> struct ao { using ac = typename an<m>::br; };
+template <class bp, class m> class bq {
+  using bu = m;
+  bp bs;
+  m bt;
+
+public:
+  template <class bn, class bv> void q(bn z, bv bw) {
+    auto s = bx(bt), by = bx(bs);
+    ap<bu>::bz(s, z, bw, by);
+  }
+};
+class ca {
+public:
+  template <class bn, class bv> void cb(bn, bv);
+};
+template <class m> ca cc(typename b<m>::cd, m &);
+template <class m> bq<d<m>, b<m>> cc(typename b<m>::cd, const m &);
+struct ce;
+template <class t, int ax> struct cf {
+  using br = typename t::br;
+  using cg = aq<long, ax>;
+  using ch = aq<long, ax>;
+};
+struct ci {
+  template <class m> static constexpr long cj = sizeof(m);
+  struct ck : j<int, g<sizeof(int)>> {};
+  template <class> static constexpr bool cl = ck::e;
+  using br = ce;
+  template <class m> using cn = ae<cl<m>, cf<ci, cj<m>>, int>;
+};
+template <class> struct an : ci::cn<long> {};
+template <class> class d : an<int> {
+  using cm = ch;
+
+public:
+  cm bl;
+};
+template <class m> auto bx(m z) { return z.bl; }
+template <class> class b : an<int> {
+  using cm = cg;
+
+public:
+  using cd = d<long>;
+  static long cu();
+  b();
+  template <class bn, class bv> b(bn, bv) {}
+  cm bl;
+};
+template <class m> auto bx(b<m> z) { return z.bl; }
+template <class m, class co> void cq(ar<m>, co, aq<bool, ar<m>::bd>);
+template <class as, class bu, class cp> as be(bu z) {
+  using cs = typename cp::bc;
+  constexpr long ax = cp::bd;
+  auto cr = bh(z);
+  aq<cs, ax> f;
+  using bn = typename p<as>::bc;
+  constexpr bool cy = sizeof(f), ct = sizeof(bn);
+  if (ct)
+    if (cy) {
+      ag cw = ai(cr);
+      return cw;
+    }
+}
+template <class as, class at> auto cv(at z) { return bf<as>(z); }
+struct G {
+  template <class m> using ch = typename ci::cn<m>::ch;
+  template <class m, unsigned long ax, class bn, class co>
+  static void bz(aq<m, ax> z, bn *, co, ch<m> cx) {
+    using da = aq<bn, sizeof(bn)>;
+    using bu = typename da::bm;
+    using bp = aq<ae<1, bool, bn>, da::bd>;
+    auto cz = cv<bu>(z);
+    cq(da(cz), ae<0, int, co>(), au<bp>(cx));
+  }
+};
+struct ce : G {};
+}
+class D {
+public:
+  D(...);
+  template <typename db> void operator<<(db);
+};
+template <class dc> dc dd;
+struct de {
+  long cu();
+};
+template <typename dc> void dg() {
+  using db = long;
+  auto df = dd<a::b<long>>;
+  using a::ak;
+  using a::al;
+  constexpr long di = 1, alignment = a::bo<a::b<long>>;
+  using dh = ae<di, decltype(al), int>;
+  dh dk, am = a::am<alignment>;
+  const a::b<long> dj;
+  de u;
+  auto dm = 0 ? u.cu() : 0;
+  float dl[dm];
+  db reference;
+  a::b<long> x;
+  auto compare = [&](long) {
+    int n;
+    a::b<long>(reference, ak);
+    for (auto i = 0; 0; ++i)
+      [] {
+        auto v = 0, w = 0;
+        return D(w, v);
+      }() << n;
+  };
+  compare(0);
+  using c = a::b<long>::cd;
+  c dn;
+  a::b y = df;
+  auto v(y);
+  cc(dn, x).cb(dl, am);
+  long i;
+  cc(dn, dj).q(&dl[dc::cu()], dk);
+  ++i;
+}
+void test() { dg<a::b<long>>(); }