From f6ac69d0d2576d2527e255c2d5904ab234e23daf Mon Sep 17 00:00:00 2001
From: Alexandre Duret-Lutz <adl@lrde.epita.fr>
Date: Mon, 21 Sep 2020 14:19:07 +0200
Subject: [PATCH] * spot/misc/common.hh: Require C++17 and simplify some
 macros.

---
 spot/misc/common.hh | 52 +++++++++------------------------------------
 1 file changed, 10 insertions(+), 42 deletions(-)

diff --git a/spot/misc/common.hh b/spot/misc/common.hh
index 0fcf9a346..9d8b58ef9 100644
--- a/spot/misc/common.hh
+++ b/spot/misc/common.hh
@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2013-2019 Laboratoire de Recherche et Développement
+// Copyright (C) 2013-2020 Laboratoire de Recherche et Développement
 // de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
@@ -31,23 +31,15 @@
 #define SPOT_UNLIKELY(expr) (expr)
 #endif
 
-#ifdef __has_cpp_attribute
-#  if __has_cpp_attribute(deprecated) && __cplusplus >= 201402L
-#    define SPOT_DEPRECATED(msg) [[deprecated(msg)]]
-#  elif __has_cpp_attribute(gnu::deprecated)
-#    define SPOT_DEPRECATED(msg) [[gnu::deprecated(msg)]]
-#  elif __has_cpp_attribute(clang::deprecated)
-#    define SPOT_DEPRECATED(msg) [[clang::deprecated(msg)]]
-#  endif
-#endif
-#ifndef SPOT_DEPRECATED
-#  ifdef __GNUC__
-#    define SPOT_DEPRECATED(msg) __attribute__ ((deprecated))
-#  elif defined(_MSC_VER)
-#    define SPOT_DEPRECATED(msg) __declspec(deprecated)
-#  else
-#    define SPOT_DEPRECATED(msg)
-#  endif
+#ifdef SWIG
+  #define SPOT_DEPRECATED(msg)
+  #define SPOT_FALLTHROUGH
+#else
+  #if __cplusplus < 201703L
+    #error C++17 compiler required
+  #endif
+  #define SPOT_DEPRECATED(msg) [[deprecated(msg)]]
+  #define SPOT_FALLTHROUGH [[fallthrough]]
 #endif
 
 #if defined _WIN32 || defined __CYGWIN__
@@ -142,30 +134,6 @@
 //   auto func(int param) SPOT_RETURN(implem_.func(param));
 #define SPOT_RETURN(code) -> decltype(code) { return code; }
 
-// We hope compilers that implement -Wimplicit-fallthrough also
-// support __has_cpp_attribute and some form of [[fallthrough]].  Do
-// not use [[fallthough]] if the code is compiled in a pre-C++17
-// standard since clang's -Wpedantic would complain that we are using
-// a feature from the future.
-#ifdef __has_cpp_attribute
-#  if __has_cpp_attribute(fallthrough) && __cplusplus > 201402L
-#    define SPOT_FALLTHROUGH [[fallthrough]]
-#  elif __has_cpp_attribute(clang::fallthrough)
-#    define SPOT_FALLTHROUGH [[clang::fallthrough]]
-#  elif __has_cpp_attribute(gnu::fallthrough)
-#    define SPOT_FALLTHROUGH [[gnu::fallthrough]]
-#  endif
-#endif
-#ifndef SPOT_FALLTHROUGH
-// Clang 3.5 does not support __has_cpp_attribute but has
-// [[clang::fallthrough]].
-#  if __clang__
-#    define SPOT_FALLTHROUGH [[clang::fallthrough]]
-#  else
-#    define SPOT_FALLTHROUGH while (0)
-#  endif
-#endif
-
 namespace spot
 {
   struct SPOT_API parse_error: public std::runtime_error