This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: C++ PATCH for c++/56567 (ICE with lambda returning init-list)
- From: Jason Merrill <jason at redhat dot com>
- To: gcc-patches List <gcc-patches at gcc dot gnu dot org>
- Date: Mon, 11 Mar 2013 12:20:20 -0400
- Subject: Re: C++ PATCH for c++/56567 (ICE with lambda returning init-list)
- References: <513A09D3.5020900@redhat.com>
On 03/08/2013 10:54 AM, Jason Merrill wrote:
My initial proposal for allowing general return type deduction allowed
deduction of std::initializer_list, which is not permitted by C++11. But
this doesn't make sense, because the underlying array will immediately
leak, so we should just give an error even in C++1y.
As pointed out in the PR, this approach was wrong because it's possible
to have an expression with std::initializer_list type; the thing
returned might not have itself been a brace-enclosed init list. So
let's catch that earlier.
Tested x86_64-pc-linux-gnu, applying to trunk.
commit 3d3cc430920cbb17be4e85742c34d51b94537a37
Author: Jason Merrill <jason@redhat.com>
Date: Mon Mar 11 12:03:31 2013 -0400
PR c++/56567
* typeck.c (check_return_expr): Disallow returning init list here.
* semantics.c (apply_deduced_return_type): Not here.
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 233765a..e909b98 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -9061,12 +9061,6 @@ apply_deduced_return_type (tree fco, tree return_type)
if (return_type == error_mark_node)
return;
- if (is_std_init_list (return_type))
- {
- error ("returning %qT", return_type);
- return_type = void_type_node;
- }
-
if (LAMBDA_FUNCTION_P (fco))
{
tree lambda = CLASSTYPE_LAMBDA_EXPR (current_class_type);
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 58295d7..58ebcc0 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -8136,6 +8136,11 @@ check_return_expr (tree retval, bool *no_warning)
"deduced to %<void%>");
type = error_mark_node;
}
+ else if (retval && BRACE_ENCLOSED_INITIALIZER_P (retval))
+ {
+ error ("returning initializer list");
+ type = error_mark_node;
+ }
else
{
if (!retval)
diff --git a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-initlist3.C b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-initlist3.C
index 029287b..f7b82ef 100644
--- a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-initlist3.C
+++ b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-initlist3.C
@@ -5,7 +5,7 @@
int main()
{
- []{ return { 1, 2 }; }(); // { dg-error "initializer_list" }
+ []{ return { 1, 2 }; }(); // { dg-error "initializer.list" }
}
// { dg-prune-output "return-statement with a value" }