From: Jean-Paul Pelteret <jppelteret@gmail.com>
Date: Sat, 1 Feb 2020 19:00:04 +0000 (+0100)
Subject: Fix SymmetricTensor and Tensor ProductType
X-Git-Tag: v9.2.0-rc1~584^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0334837011498c395a9de03cbe2fadbb61faacc9;p=dealii.git

Fix SymmetricTensor and Tensor ProductType

Fixes a compiler error on the old Apple Clang 8.0.0 compiler, where the product type between complex numbers and tensors could not be determined.
---

diff --git a/include/deal.II/base/symmetric_tensor.h b/include/deal.II/base/symmetric_tensor.h
index ca531dfa5f..f90e3e4d79 100644
--- a/include/deal.II/base/symmetric_tensor.h
+++ b/include/deal.II/base/symmetric_tensor.h
@@ -72,6 +72,24 @@ DEAL_II_CONSTEXPR inline DEAL_II_ALWAYS_INLINE Number
 
 namespace internal
 {
+  template <int rank, int dim, typename T, typename U>
+  struct ProductTypeImpl<SymmetricTensor<rank, dim, T>, std::complex<U>>
+  {
+    using type =
+      SymmetricTensor<rank,
+                      dim,
+                      std::complex<typename ProductType<T, U>::type>>;
+  };
+
+  template <typename T, int rank, int dim, typename U>
+  struct ProductTypeImpl<std::complex<T>, SymmetricTensor<rank, dim, U>>
+  {
+    using type =
+      SymmetricTensor<rank,
+                      dim,
+                      std::complex<typename ProductType<T, U>::type>>;
+  };
+
   /**
    * A namespace for functions and classes that are internal to how the
    * SymmetricTensor class (and its associate functions) works.
diff --git a/include/deal.II/base/tensor.h b/include/deal.II/base/tensor.h
index a1fbcdc4b8..a1952271f1 100644
--- a/include/deal.II/base/tensor.h
+++ b/include/deal.II/base/tensor.h
@@ -755,6 +755,20 @@ private:
 
 namespace internal
 {
+  template <int rank, int dim, typename T, typename U>
+  struct ProductTypeImpl<Tensor<rank, dim, T>, std::complex<U>>
+  {
+    using type =
+      Tensor<rank, dim, std::complex<typename ProductType<T, U>::type>>;
+  };
+
+  template <typename T, int rank, int dim, typename U>
+  struct ProductTypeImpl<std::complex<T>, Tensor<rank, dim, U>>
+  {
+    using type =
+      Tensor<rank, dim, std::complex<typename ProductType<T, U>::type>>;
+  };
+
   /**
    * The structs below are needed to initialize nested Tensor objects.
    * Also see numbers.h for another specialization.