add comment for complex casting and C++ standard

ginkgo-project · May 19, 2021 · 1a12300 · 1a12300
1 parent c8666d1
commit 1a12300
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/omp/components/atomic.hpp b/omp/components/atomic.hpp
@@ -58,6 +58,8 @@ template <typename ValueType,
           std::enable_if_t<is_complex<ValueType>()> * = nullptr>
 void atomic_add(ValueType &out, ValueType val)
 {
+    // The C++ standard explicitly allows casting complex<double>* to double*
+    // [complex.numbers.general]
     auto values = reinterpret_cast<gko::remove_complex<ValueType> *>(&out);
 #pragma omp atomic
     values[0] += real(val);