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From: "daniel.kruegler at googlemail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/55002] trailing return type is rejected in function signature
Date: Sat, 20 Oct 2012 20:24:00 -0000	[thread overview]
Message-ID: <bug-55002-4-oclvQcfQaE@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-55002-4@http.gcc.gnu.org/bugzilla/>


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55002

Daniel Krügler <daniel.kruegler at googlemail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |daniel.kruegler at
                   |                            |googlemail dot com

--- Comment #2 from Daniel Krügler <daniel.kruegler at googlemail dot com> 2012-10-20 20:24:19 UTC ---
Your issue looks invalid to me, because you are never providing a pointer to
function declarator. 

Lets look first at your simplified example:

auto (*ff) -> int (int)

This would be an invalid function declarator, because there is (a) no parameter
list and (b) the return type is a function type int(int), which is never
possible. I can only assume you mean

int f(auto (*ff)(int) -> int) {
  return ff(1);
}

and this is accepted. 

A similar defect is in your original code, where the only valid form would be

template<class T, size_t N> size_t   
apply (const T (&A)[N], auto (*f)(const T (&)[N]) -> size_t)
{ return   f(A); }


which is also accepted.


  parent reply	other threads:[~2012-10-20 20:24 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-20 19:01 [Bug c++/55002] New: " leonid at volnitsky dot com
2012-10-20 19:20 ` [Bug c++/55002] " leonid at volnitsky dot com
2012-10-20 20:24 ` daniel.kruegler at googlemail dot com [this message]
2012-10-20 22:56 ` paolo.carlini at oracle dot com

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