[libcxx-commits] [libcxx] [libc++] Constrain additional overloads of `pow` for `complex` harder (PR #110235)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,106 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// <complex>
+
+//  template<class T, class U> complex<__promote<T, U>::type> pow(const complex<T>&, const U&);
+//  template<class T, class U> complex<__promote<T, U>::type> pow(const complex<T>&, const complex<U>&);
+//  template<class T, class U> complex<__promote<T, U>::type> pow(const T&, const complex<U>&);
+
+// Test that these additional overloads are free from catching std::complex<non-floating-point>,
+// which is expected by several 3rd party libraries, see https://github.com/llvm/llvm-project/issues/109858.
+
+#include <cassert>
+#include <cmath>
+#include <complex>
+#include <type_traits>
+
+#include "test_macros.h"
+
+namespace usr {
+struct usr_tag {};
+
+template <class T, class U>
+TEST_CONSTEXPR
----------------
ldionne wrote:

`constexpr` here doesn't really buy you anything in the test. I'd suggest either dropping `TEST_CONSTEXPR` here or running the test both in constexpr and non-constexpr context (which doesn't seem to add much value).

https://github.com/llvm/llvm-project/pull/110235