[Bug c++/68942] overly strict use of deleted function before argument-dependent lookup (ADL)

2022-10-06 Thread pinskia at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68942

Andrew Pinski  changed:

   What|Removed |Added

 CC||physhivam at gmail dot com

--- Comment #5 from Andrew Pinski  ---
*** Bug 107175 has been marked as a duplicate of this bug. ***

[Bug c++/68942] overly strict use of deleted function before argument-dependent lookup (ADL)

2021-05-03 Thread cvs-commit at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68942

--- Comment #4 from CVS Commits  ---
The master branch has been updated by Patrick Palka :

https://gcc.gnu.org/g:eef4fa6968ae0682679c27dae06409db3d113d5d

commit r12-391-geef4fa6968ae0682679c27dae06409db3d113d5d
Author: Patrick Palka 
Date:   Mon May 3 13:35:26 2021 -0400

c++: mark_used and ADL with template-id [PR100344]

My r11-295 patch for PR68942 didn't consider that the callee of an
ADL-eligible function call can be a TEMPLATE_ID_EXPR, and we don't want
to disable mark_used when substituting into the template arguments of
this TEMPLATE_ID_EXPR because the arguments are clearly used regardless
of the outcome of ADL.  In the first testcase below, this oversight
causes us to trip over the assert in build_call_a for the call to
find_index because the function no longer had its TREE_USED bit set
from mark_used.

So this patch restricts the original fix to disable mark_used only when
the callee is a FUNCTION_DECL, which seems to be the only case that
matters for PR68942.  For instance, in the second testcase below we
already don't mark_used the deleted function specialization even before
r11-295.

gcc/cp/ChangeLog:

PR c++/68942
PR c++/100344
* pt.c (tsubst_copy_and_build) : Set tf_conv
only when the callee is a FUNCTION_DECL.

gcc/testsuite/ChangeLog:

PR c++/68942
PR c++/100344
* g++.dg/template/call8.C: New test.
* g++.dg/template/koenig12a.C: New test.

[Bug c++/68942] overly strict use of deleted function before argument-dependent lookup (ADL)

2021-04-29 Thread ppalka at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68942

Patrick Palka  changed:

   What|Removed |Added

 Status|ASSIGNED|RESOLVED
 Resolution|--- |FIXED
   Target Milestone|--- |12.0

--- Comment #3 from Patrick Palka  ---
Fixed for GCC 12, thanks for the bug report.

[Bug c++/68942] overly strict use of deleted function before argument-dependent lookup (ADL)

2021-04-29 Thread cvs-commit at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68942

--- Comment #2 from CVS Commits  ---
The master branch has been updated by Patrick Palka :

https://gcc.gnu.org/g:efeca0ac4155b76ce713155f190422aac20537c5

commit r12-295-gefeca0ac4155b76ce713155f190422aac20537c5
Author: Patrick Palka 
Date:   Thu Apr 29 13:43:00 2021 -0400

c++: Overeager use of deleted function before ADL [PR68942]

Here, at template definition time, ordinary name lookup for 'foo(t)'
finds only the deleted function, and so we form a CALL_EXPR thereof.
Later at instantiation time, when initially substituting into this
CALL_EXPR with T=N::A, we end up calling mark_used on this deleted
function (since it's the only function in the overload set), triggering
a bogus "use of deleted function error", before we get to augment the
overload set via ADL.

This patch fixes this issue by using the tf_conv flag to disable
mark_used during the initial substitution into the callee of a
CALL_EXPR when KOENIG_P, since at this point we're still figuring out
which functions are candidates.

gcc/cp/ChangeLog:

PR c++/68942
* pt.c (tsubst_copy_and_build) : When KOENIG_P,
set tf_conv during the initial substitution into the function.

gcc/testsuite/ChangeLog:

PR c++/68942
* g++.dg/template/koenig12.C: New test.

[Bug c++/68942] overly strict use of deleted function before argument-dependent lookup (ADL)

2021-04-28 Thread ppalka at gcc dot gnu.org via Gcc-bugs 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68942

Patrick Palka  changed:

   What|Removed |Added

   Assignee|unassigned at gcc dot gnu.org  |ppalka at gcc dot 
gnu.org
 Status|NEW |ASSIGNED
 CC||ppalka at gcc dot gnu.org

[Bug c++/68942] overly strict use of deleted function before argument-dependent lookup (ADL)

2018-10-20 Thread jbassett271 at gmail dot com 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68942

Justin Bassett  changed:

   What|Removed |Added

 CC||jbassett271 at gmail dot com

--- Comment #1 from Justin Bassett  ---
I believe the following is another case of this bug:
https://godbolt.org/z/9r9QdS . MSVC and Clang compile this fine; GCC only
compiles it fine if the `= delete` is not present. It's really weird that GCC
selects the deleted `begin()` even though it does not take an argument.

namespace foo {
namespace detail {
void begin() = delete;
}

inline auto begin = [](auto&& a) {
using detail::begin;
return begin(a);
};
}

#include 

int main() {
return *foo::begin(std::array{1, 2});
}


Error message:

: In instantiation of 'foo:: [with auto:1 =
std::array]':

:15:48:   required from here

:8:21: error: use of deleted function 'void foo::detail::begin()'

 return begin(a);

~^~~

:3:14: note: declared here

 void begin() = delete;

  ^

: In function 'int main()':

:15:23: error: void value not ignored as it ought to be

 return *foo::begin(std::array{1, 2});

 ~~^~

[Bug c++/68942] overly strict use of deleted function before argument-dependent lookup (ADL)

2015-12-16 Thread redi at gcc dot gnu.org 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68942

Jonathan Wakely  changed:

   What|Removed |Added

   Keywords||rejects-valid
 Status|UNCONFIRMED |NEW
   Last reconfirmed||2015-12-16
 Ever confirmed|0   |1