PR c++/60364 - noreturn after first decl not diagnosed.

[thirdparty/gcc.git] / gcc / cp / decl.c

diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 0a3ef452536fa836c3b37e227304ebccd878ee41..85f96f7373966a0ee9dd45c02d33720928795692 100644 (file)
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -1922,10 +1922,29 @@ duplicate_decls (tree newdecl, tree olddecl, bool newdecl_is_friend)
 
   if (TREE_CODE (newdecl) == FUNCTION_DECL)
     {
-      if (merge_attr && diagnose_mismatched_attributes (olddecl, newdecl))
-       inform (olddecl_loc, DECL_INITIAL (olddecl)
-               ? G_("previous definition of %qD here")
-               : G_("previous declaration of %qD here"), olddecl);
+      if (merge_attr)
+       {
+         if (diagnose_mismatched_attributes (olddecl, newdecl))
+           inform (olddecl_loc, DECL_INITIAL (olddecl)
+                   ? G_("previous definition of %qD here")
+                   : G_("previous declaration of %qD here"), olddecl);
+
+         /* [dcl.attr.noreturn]: The first declaration of a function shall
+            specify the noreturn attribute if any declaration of that function
+            specifies the noreturn attribute.  */
+         tree a;
+         if (TREE_THIS_VOLATILE (newdecl)
+             && !TREE_THIS_VOLATILE (olddecl)
+             /* This applies to [[noreturn]] only, not its GNU variants.  */
+             && (a = lookup_attribute ("noreturn", DECL_ATTRIBUTES (newdecl)))
+             && cxx11_attribute_p (a)
+             && get_attribute_namespace (a) == NULL_TREE)
+           {
+             error_at (newdecl_loc, "function %qD declared %<[[noreturn]]%> "
+                       "but its first declaration was not", newdecl);
+             inform (olddecl_loc, "previous declaration of %qD", olddecl);
+           }
+       }
 
       /* Now that functions must hold information normally held
         by field decls, there is extra work to do so that