[clang] Error (with diagnostic) on valid after #90574

[dcci]

namespace {
typedef char a;
template <typename b> struct ai {
  typedef b aj;
  typedef ai ak;
  aj operator*();
  ak operator++();
  friend bool operator==(ak, ak);
};
template <typename, typename, typename, typename> class am {
  typedef a an;

public:
  typedef ai<an> ao;
};
template <typename ap, typename c = ap> class aq {
  typedef ap ar;
  typedef ap an;
  typedef c as;
  typedef am<ar, an, an, as> at;

public:
  typedef at::ao av;
  av begin();
  av end();
};
namespace {
namespace {
a aw() {
  aq<a> ax;
  for (auto module : ax)
    ;
}
} // namespace
} // namespace
} // namespace

clang patatino.cpp -std=c++20 -c

The patch got reverted, but this is the testcase.

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Davide Italiano (dcci)

``` namespace { typedef char a; template <typename b> struct ai { typedef b aj; typedef ai ak; aj operator*(); ak operator++(); friend bool operator==(ak, ak); }; template <typename, typename, typename, typename> class am { typedef a an;

public:
typedef ai<an> ao;
};
template <typename ap, typename c = ap> class aq {
typedef ap ar;
typedef ap an;
typedef c as;
typedef am<ar, an, an, as> at;

public:
typedef at::ao av;
av begin();
av end();
};
namespace {
namespace {
a aw() {
aq<a> ax;
for (auto module : ax)
;
}
} // namespace
} // namespace
} // namespace

`clang patatino.cpp -std=c++20 -c`

The patch got reverted, but this is the testcase.
</details>

[yronglin]

Thank you report this.

[dcci]

Looks like this one got fixed.