remove check for fold expressions

amdis/common/ForEach.hpp

@@ -9,33 +9,17 @@ namespace AMDiS
 {
   namespace Tools
   {
-    namespace Impl_
-    {
-      template <class T>
-      void ignored_evaluation(std::initializer_list<T>&&) { /* do nothing */ }
-    }
-
     template <class Functor, class... Args>
     constexpr void for_variadic(Functor&& f, Args&&... args)
     {
-#if AMDIS_HAS_CXX_FOLD_EXPRESSIONS
       (f(FWD(args)),...);
-#else
-      Impl_::ignored_evaluation<int>({0, (f(FWD(args)), 0)...});
-#endif
     }
 
     template <std::size_t... I, class Tuple, class Functor>
     constexpr void for_each(std::index_sequence<I...>, Tuple&& tuple, Functor&& f)
     {
       using std::get;
-#if AMDIS_HAS_EXPANSION_STATEMENTS
-      for... (auto&& t : tuple) { f(FWD(t)); }
-#elif AMDIS_HAS_CXX_FOLD_EXPRESSIONS
       (f(get<I>(tuple)),...);
-#else
-      Impl_::ignored_evaluation<int>({0, (f(get<I>(tuple)), 0)...});
-#endif
     }
 
     template <class Tuple, class Functor>
@@ -48,11 +32,7 @@ namespace AMDiS
     template <std::size_t I0 = 0, std::size_t... I, class Functor>
     constexpr void for_range(std::index_sequence<I...>, Functor&& f)
     {
-#if AMDIS_HAS_CXX_FOLD_EXPRESSIONS
       (f(index_t<I0+I>{}),...);
-#else
-      Impl_::ignored_evaluation<int>({0, (f(index_t<I0+I>{}), 0)...});
-#endif
     }
 
     template <std::size_t I0, std::size_t I1, class Functor>

amdis/common/Math.hpp

@@ -93,31 +93,11 @@ namespace AMDiS
       return 0.0;
     }
 
-#ifndef AMDIS_HAS_CXX_FOLD_EXPRESSIONS
-    template <class T>
-    constexpr auto const& sum(T const& t)
-    {
-      return t;
-    }
-
-    template <class T0, class T1>
-    constexpr auto sum(T0 const& t0, T1 const& t1)
-    {
-      return t0 + t1;
-    }
-
-    template <class T0, class... Ts>
-    constexpr auto sum(T0 const& t0, Ts const&... ts)
-    {
-      return t0 + sum(ts...);
-    }
-#else
     template <class... Ts>
     constexpr auto sum(Ts const&... ts)
     {
       return (ts + ...);
     }
-#endif
 
   } // end namespace Math
 

amdis/operations/Arithmetic.hpp

@@ -99,19 +99,11 @@ namespace AMDiS
     /// Functor that represents A*B
     struct Multiplies
     {
-#ifdef AMDIS_HAS_CXX_FOLD_EXPRESSIONS
       template <class... Ts>
       constexpr auto operator()(Ts const&... ts) const
       {
         return (ts * ...);
       }
-#else
-      template <class T, class S>
-      constexpr auto operator()(T const& lhs, S const& rhs) const
-      {
-        return lhs * rhs;
-      }
-#endif
     };
 
 

cmake/modules/AmdisCXXFeatures.cmake

@@ -2,20 +2,6 @@ include(CheckCXXSourceCompiles)
 
 set(CMAKE_REQUIRED_FLAGS "-pedantic-errors")
 
-# fold expressions (a + ...)
-check_cxx_source_compiles("
-  template <class... Args>
-  int f(Args... args)
-  {
-    return (args + ...);
-  }
-  int main()
-  {
-    f(0,1,2,3,4,5);
-  }
-"  AMDIS_HAS_CXX_FOLD_EXPRESSIONS
-)
-
 check_cxx_source_compiles("
   #include <iostream>
   #include <tuple>

config.h.cmake

@@ -53,7 +53,6 @@
 #cmakedefine AMDIS_HAS_PETSC 1
 
 /* some detected compiler features may be used in AMDiS */
-#cmakedefine AMDIS_HAS_CXX_FOLD_EXPRESSIONS 1
 #cmakedefine AMDIS_HAS_EXPANSION_STATEMENTS 1
 #cmakedefine AMDIS_HAS_CXX_AUTO_TEMPLATE_PARAMETER 1