re PR c++/65775 (Late-specified return type bypasses return type checks (qualified, function, array))

/cp
2017-07-03  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/65775
	* decl.c (grokdeclarator): Move checks on function return type after
	the splice_late_return_type call; if declspecs->locations[ds_type_spec]
	is UNKNOWN_LOCATION fall back to input_location.

/testsuite
2017-07-03  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/65775
	* g++.dg/cpp0x/trailing14.C: New.

From-SVN: r249935

4 files changed, 59 insertions, 28 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 4754877..189edcb 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,10 @@
+2017-07-03  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/65775
+	* decl.c (grokdeclarator): Move checks on function return type after
+	the splice_late_return_type call; if declspecs->locations[ds_type_spec]
+	is UNKNOWN_LOCATION fall back to input_location.
+
 2017-07-03  David Malcolm  <dmalcolm@redhat.com>
 
 	* parser.c (enum required_token): Fix spelling of
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 62877dc..d5b758a 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -9992,6 +9992,8 @@ grokdeclarator (const cp_declarator *declarator,
 						      declspecs->locations);
   if (typespec_loc == UNKNOWN_LOCATION)
     typespec_loc = declspecs->locations[ds_type_spec];
+  if (typespec_loc == UNKNOWN_LOCATION)
+    typespec_loc = input_location;
 
   /* Look inside a declarator for the name being declared
      and get it as a string, for an error message.  */
@@ -10822,33 +10824,7 @@ grokdeclarator (const cp_declarator *declarator,
 	    tree arg_types;
 	    int funcdecl_p;
 
-	    /* Declaring a function type.
-	       Make sure we have a valid type for the function to return.  */
-
-	    if (type_quals != TYPE_UNQUALIFIED)
-	      {
-		if (SCALAR_TYPE_P (type) || VOID_TYPE_P (type))
-		  {
-		    warning_at (typespec_loc, OPT_Wignored_qualifiers, "type "
-				"qualifiers ignored on function return type");
-		  }
-		/* We now know that the TYPE_QUALS don't apply to the
-		   decl, but to its return type.  */
-		type_quals = TYPE_UNQUALIFIED;
-	      }
-
-	    /* Error about some types functions can't return.  */
-
-	    if (TREE_CODE (type) == FUNCTION_TYPE)
-	      {
-		error ("%qs declared as function returning a function", name);
-		return error_mark_node;
-	      }
-	    if (TREE_CODE (type) == ARRAY_TYPE)
-	      {
-		error ("%qs declared as function returning an array", name);
-		return error_mark_node;
-	      }
+	    /* Declaring a function type.  */
 
 	    input_location = declspecs->locations[ds_type_spec];
 	    abstract_virtuals_error (ACU_RETURN, type);
@@ -10956,7 +10932,35 @@ grokdeclarator (const cp_declarator *declarator,
 	      return error_mark_node;
 
 	    if (late_return_type)
-	      late_return_type_p = true;
+	      {
+		late_return_type_p = true;
+		type_quals = cp_type_quals (type);
+	      }
+
+	    if (type_quals != TYPE_UNQUALIFIED)
+	      {
+		if (SCALAR_TYPE_P (type) || VOID_TYPE_P (type))
+		  warning_at (typespec_loc, OPT_Wignored_qualifiers, "type "
+			      "qualifiers ignored on function return type");
+		/* We now know that the TYPE_QUALS don't apply to the
+		   decl, but to its return type.  */
+		type_quals = TYPE_UNQUALIFIED;
+	      }
+
+	    /* Error about some types functions can't return.  */
+
+	    if (TREE_CODE (type) == FUNCTION_TYPE)
+	      {
+		error_at (typespec_loc, "%qs declared as function returning "
+			  "a function", name);
+		return error_mark_node;
+	      }
+	    if (TREE_CODE (type) == ARRAY_TYPE)
+	      {
+		error_at (typespec_loc, "%qs declared as function returning "
+			  "an array", name);
+		return error_mark_node;
+	      }
 
 	    if (ctype == NULL_TREE
 		&& decl_context == FIELD
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 681783f..03f9357 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2017-07-03  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/65775
+	* g++.dg/cpp0x/trailing14.C: New.
+
 2017-07-03  Dominique d'Humieres  <dominiq@lps.ens.fr>
 
 	PR testsuite/79866
diff --git a/gcc/testsuite/g++.dg/cpp0x/trailing14.C b/gcc/testsuite/g++.dg/cpp0x/trailing14.C
new file mode 100644
index 0000000..2544d0b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/trailing14.C
@@ -0,0 +1,15 @@
+// PR c++/65775
+// { dg-do compile { target c++11 } }
+// { dg-options "-Wignored-qualifiers" }
+
+using Qi = int const volatile;
+Qi q1();           // { dg-warning "1: type qualifiers ignored" }
+auto q2() -> Qi;   // { dg-warning "1: type qualifiers ignored" }
+
+using Fi = int();
+Fi f1();           // { dg-error "1: 'f1' declared as function returning a function" }
+auto f2() -> Fi;   // { dg-error "1: 'f2' declared as function returning a function" }
+
+using Ai = int[5];
+Ai a1();           // { dg-error "1: 'a1' declared as function returning an array" }
+auto a2() -> Ai;   // { dg-error "1: 'a2' declared as function returning an array" }