From 0cfabb3780b23de06e8fd52bfe15b2aea7b56f42 Mon Sep 17 00:00:00 2001
From: Ville Voutilainen <ville.voutilainen@gmail.com>
Date: Mon, 20 Apr 2015 23:44:25 +0300
Subject: [PATCH] Reject trailing return type for an operator auto().

	* decl.c (grokdeclarator): Reject trailing return types for
	all conversion operators, don't handle conversion operators
	in the previous checks that deal with auto.

From-SVN: r222248
---
 gcc/cp/ChangeLog                   | 7 +++++++
 gcc/cp/decl.c                      | 7 +++++--
 gcc/testsuite/g++.dg/cpp0x/auto9.C | 4 ++--
 3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 08d1010b64d..f7da7c61b0d 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,10 @@
+2015-04-20  Ville Voutilainen  <ville.voutilainen@gmail.com>
+
+	Reject trailing return type for an operator auto().
+	* decl.c (grokdeclarator): Reject trailing return types for
+	all conversion operators, don't handle conversion operators
+	in the previous checks that deal with auto.
+
 2015-04-20  Ilya Verbin  <ilya.verbin@intel.com>
 
 	* parser.c (cp_parser_omp_target_update): Add missed %> to error_at ().
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index b920fe7da0b..29d6e73ca31 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -9782,7 +9782,7 @@ grokdeclarator (const cp_declarator *declarator,
 			    virtualp = false;
 			  }
 		      }
-		    else if (!is_auto (type))
+		    else if (!is_auto (type) && sfk != sfk_conversion)
 		      {
 			error ("%qs function with trailing return type has"
 			       " %qT as its type rather than plain %<auto%>",
@@ -9790,7 +9790,8 @@ grokdeclarator (const cp_declarator *declarator,
 			return error_mark_node;
 		      }
 		  }
-		else if (declarator->u.function.late_return_type)
+		else if (declarator->u.function.late_return_type
+			 && sfk != sfk_conversion)
 		  {
 		    if (cxx_dialect < cxx11)
 		      /* Not using maybe_warn_cpp0x because this should
@@ -9899,6 +9900,8 @@ grokdeclarator (const cp_declarator *declarator,
 		    maybe_warn_cpp0x (CPP0X_EXPLICIT_CONVERSION);
 		    explicitp = 2;
 		  }
+		if (late_return_type_p)
+		  error ("a conversion function cannot have a trailing return type");
 	      }
 
 	    arg_types = grokparms (declarator->u.function.parameters,
diff --git a/gcc/testsuite/g++.dg/cpp0x/auto9.C b/gcc/testsuite/g++.dg/cpp0x/auto9.C
index 0c0f39f02c6..83efbaa534e 100644
--- a/gcc/testsuite/g++.dg/cpp0x/auto9.C
+++ b/gcc/testsuite/g++.dg/cpp0x/auto9.C
@@ -21,8 +21,8 @@ struct A
 
 struct A2
 {
-  operator auto () -> int;			// { dg-error "invalid use of" "" { target { ! c++14 } } }
-  operator auto *() -> int;			// { dg-error "auto" }
+  operator auto () -> int;			// { dg-error "invalid use of|trailing return type" }
+  operator auto*() -> int;			// { dg-error "invalid use of|trailing return type" }
 };
 
 template <typename> struct B