Merge pull request #16457 from bangerth/assume

[C++23] When using C++23, use [[assume]] attribute.
dealii · Feb 19, 2024 · 2e2dd3f · 2e2dd3f
2 parents cc045c7 + 46c0e6c
commit 2e2dd3f
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Showing 2 changed files with 11 additions and 15 deletions.
diff --git a/include/deal.II/base/config.h.in b/include/deal.II/base/config.h.in
@@ -183,29 +183,24 @@
  * attribute for older standards we rely on compiler intrinsics when
  * available.
  */
-#if defined(__clang__)
-#  define DEAL_II_CXX23_ASSUME(expr) __builtin_assume(static_cast<bool>(expr))
-#elif defined(__GNUC__) && !defined(__ICC) && __GNUC__ >= 13
-#  define DEAL_II_CXX23_ASSUME(expr)                                   \
-    do                                                                 \
-      {                                                                \
-        _Pragma("GCC diagnostic push")                                 \
-          _Pragma("GCC diagnostic ignored \"-Wimplicit-fallthrough\"") \
-            [[assume(expr)]];                                          \
-        _Pragma("GCC diagnostic pop")                                  \
-      }                                                                \
-    while (false)
-#elif defined(_MSC_VER) || defined(__ICC)
-#  define DEAL_II_CXX23_ASSUME(expr) __assume(expr);
+#ifdef DEAL_II_HAVE_CXX23
+#  define define DEAL_II_ASSUME(expr) [[assume(expr)]]
 #else
+#  if defined(__clang__)
+#    define DEAL_II_CXX23_ASSUME(expr) __builtin_assume(static_cast<bool>(expr))
+#  elif defined(_MSC_VER) || defined(__ICC)
+#    define DEAL_II_CXX23_ASSUME(expr) __assume(expr);
+#  else
 /* no way with GCC to express this without evaluating 'expr' */
-#  define DEAL_II_CXX23_ASSUME(expr) \
+#    define DEAL_II_CXX23_ASSUME(expr) \
     do                               \
       {                              \
       }                              \
     while (false)
+#  endif
 #endif
 
+
 /**
  * Macro indicating that the current feature will be removed in a future
  * release.

diff --git a/include/deal.II/base/exceptions.h b/include/deal.II/base/exceptions.h
@@ -1527,6 +1527,7 @@ namespace deal_II_exceptions
 } /*namespace deal_II_exceptions*/
 
 
+
 /**
  * A macro that serves as the main routine in the exception mechanism for debug
  * mode error checking. It asserts that a certain condition is fulfilled,