[Bug libstdc++/37907] New: type_trait: missing is_standard_layout

[Bug libstdc++/37907] New: type_trait: missing is_standard_layout

[bkoz at gcc dot gnu dot org]

Already known, can be considered a feature request.

#include <type_traits>

struct b
{
  int b;
  b() = default;
  b(const b&) = delete;
};

void test01()
{
  typedef b     test_type;

  typedef std::is_standard_layout<test_type> standard_layout_p;

  static_assert(standard_layout_p::value, "not standard_layout");
}


-- 
           Summary: type_trait: missing is_standard_layout
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bkoz at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37907

[Bug libstdc++/37907] type_trait: missing is_standard_layout

[paolo dot carlini at oracle dot com]

------- Comment #1 from paolo dot carlini at oracle dot com  2008-10-24 08:53 -------
The bulk of this is C++ front-end of course...


-- 

paolo dot carlini at oracle dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|type_trait: missing         |type_trait: missing
                   |is_standard_layout          |is_standard_layout


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37907

[Bug libstdc++/37907] [c++0x] support for std::is_standard_layout

[bkoz at gcc dot gnu dot org]

------- Comment #2 from bkoz at gcc dot gnu dot org  2009-01-28 20:35 -------

Adjust summary, change to enhancement. 

I would really like to use std::is_standard_layout in the testsuite, so that
these requirements for <cstdatomic>, <mutex>, and <condition_variable> can be
validated for libstdc++ sources. The requirements/limitations for standard
layout types limits some designs, like derived mutexes. Tracking it in the
testsuite would be optimal.

I don't see a way to use existing C++0x type_traits to accomplish the same
thing.


-- 

bkoz at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jason at gcc dot gnu dot org
           Severity|normal                      |enhancement
            Summary|type_trait: missing         |[c++0x] support for
                   |is_standard_layout          |std::is_standard_layout


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37907

[Bug libstdc++/37907] [c++0x] support for std::is_standard_layout

[jason at gcc dot gnu dot org]

-- 

jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jason at gcc dot gnu dot org
                   |dot org                     |
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-07-15 13:57:51
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37907

[Bug libstdc++/37907] [c++0x] support for std::is_standard_layout

[jason at gcc dot gnu dot org]

------- Comment #3 from jason at gcc dot gnu dot org  2009-07-16 20:36 -------
Subject: Bug 37907

Author: jason
Date: Thu Jul 16 20:36:10 2009
New Revision: 149721

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=149721
Log:
        PR libstdc++/37907
        Support std::is_standard_layout and std::is_trivial traits,
        change POD to C++0x version (except for layout).
        * gcc/c-common.c (c_common_reswords): Add __is_standard_layout
        and __is_trivial.
        * gcc/c-common.h (enum rid): Add RID_IS_STD_LAYOUT and RID_IS_TRIVIAL.
        * gcc/cp/cp-tree.h (enum cp_trait_kind): Add CPTK_IS_STD_LAYOUT,
        CPTK_IS_TRIVIAL.
        (struct lang_type_class): Add non_std_layout.
        (CLASSTYPE_NON_STD_LAYOUT): New.
        * gcc/cp/class.c (check_bases): Set it.
        (check_field_decls): Likewise.
        (check_bases_and_members): Likewise.
        * gcc/cp/parser.c (cp_parser_primary_expression): Handle
RID_IS_STD_LAYOUT,
        RID_IS_TRIVIAL.
        (cp_parser_trait_expr): Likewise.
        * gcc/cp/semantics.c (trait_expr_value): Handle CPTK_IS_STD_LAYOUT,
        CPTK_IS_TRIVIAL.
        (finish_trait_expr): Likewise.
        * gcc/cp/tree.c (scalarish_type_p, trivial_type_p, std_layout_type_p):
New.
        (pod_type_p): Use them.
        * gcc/cp/typeck.c (build_class_member_access_expr): Check
        CLASSTYPE_NON_STD_LAYOUT rather than CLASSTYPE_NON_POD_P.
        * libstdc++-v3/include/std/type_traits: Add is_standard_layout,
is_trivial.

Added:
    trunk/gcc/doc/implement-cxx.texi
    trunk/gcc/testsuite/g++.dg/cpp0x/std-layout1.C
    trunk/gcc/testsuite/g++.dg/cpp0x/trivial1.C
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/Makefile.in
    trunk/gcc/c-common.c
    trunk/gcc/c-common.h
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/call.c
    trunk/gcc/cp/class.c
    trunk/gcc/cp/cp-tree.h
    trunk/gcc/cp/cxx-pretty-print.c
    trunk/gcc/cp/decl.c
    trunk/gcc/cp/init.c
    trunk/gcc/cp/parser.c
    trunk/gcc/cp/semantics.c
    trunk/gcc/cp/tree.c
    trunk/gcc/cp/typeck.c
    trunk/gcc/doc/gcc.texi
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/g++.dg/ext/has_nothrow_assign.C
    trunk/gcc/testsuite/g++.dg/ext/has_nothrow_copy-1.C
    trunk/gcc/testsuite/g++.dg/ext/has_trivial_assign.C
    trunk/gcc/testsuite/g++.dg/ext/has_trivial_copy.C
    trunk/gcc/testsuite/g++.dg/ext/is_pod.C
    trunk/gcc/testsuite/g++.dg/other/offsetof3.C
    trunk/gcc/testsuite/g++.dg/overload/ellipsis1.C
    trunk/gcc/testsuite/g++.dg/warn/var-args1.C
    trunk/gcc/testsuite/g++.old-deja/g++.brendan/crash63.C
    trunk/gcc/testsuite/g++.old-deja/g++.brendan/crash64.C
    trunk/gcc/testsuite/g++.old-deja/g++.brendan/overload8.C
    trunk/gcc/testsuite/g++.old-deja/g++.other/vaarg3.C
    trunk/gcc/testsuite/g++.old-deja/g++.pt/vaarg3.C
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/include/std/type_traits
   
trunk/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc
   
trunk/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37907

[Bug libstdc++/37907] [c++0x] support for std::is_standard_layout

[jason at gcc dot gnu dot org]

------- Comment #4 from jason at gcc dot gnu dot org  2009-07-16 22:11 -------
Fixed for 4.5.0.


-- 

jason at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37907

[Bug libstdc++/37907] [c++0x] support for std::is_standard_layout

[paolo dot carlini at oracle dot com]

-- 

paolo dot carlini at oracle dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37907