[
https://issues.apache.org/jira/browse/STDCXX-983?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12610069#action_12610069
]
Travis Vitek commented on STDCXX-983:
-------------------------------------
This is the documentation for the helper (taken from
[here|http://gcc.gnu.org/onlinedocs/gcc-4.3.0/gcc/Type-Traits.html#Type-Traits])
__is_pod (type){quote}If type is a cv POD type ([basic.types]) then the trait
is true, else it is false. Requires: type shall be a complete type, an array of
unknown bound or is a void type.{quote}
Here are the pertenent sections of the standard
3.9 p9{quote}Scalar types, POD classes (clause 9), arrays of such types and
cv-qualified versions of these types (3.9.3) are collectively called POD types.
Scalar types, trivial class types (clause 9), arrays of such types and
cv-qualified versions of these types (3.9.3) are collectively called trivial
types. Scalar types, standard-layout class types (clause 9), arrays of such
types and cv-qualified versions of these types (3.9.3) are collectively called
standard-layout types.{quote}
9 p5{quote}a trivial class is a class that
-- has a trivial default constructor
-- has a trivial copy constructor
-- has a trivial copy assignment operator
-- has a trivial destructor
{quote}
9 p6{quote}a standard-layout class is a class that
-- has no non-static data members of type non-standard-layout class
(or array of such types) or reference
-- has no virtual functions and no virtual base classes
-- has the same access control for all non-static data members
-- has no non-standard-layout base classes
-- either has no non-static data members in the most-derived class
and at most one base class with non-static data members, or has no base classes
with non-static data members
-- has no base classes of the same type as the first non-static data
member
{quote}
9 p9{quote}a POD struct is a class that is both a trivial class and a
standard-layout class, and has no non-static data members of type non-POD
struct, non-POD union (or array of such types). Similarly, a POD union is a
union that is both a trivial class and a standard layout class, and has no
non-static data members of type non-POD struct, non-POD union (or array of such
types).A POD class is a class that is either a POD struct or a POD union.{quote}
> [Linux/gcc] 20.meta.unary.prop.cpp fails is_pod assertions
> ----------------------------------------------------------
>
> Key: STDCXX-983
> URL: https://issues.apache.org/jira/browse/STDCXX-983
> Project: C++ Standard Library
> Issue Type: Bug
> Components: TR1.4 - Metaprogramming and Type Traits
> Affects Versions: 4.3
> Environment: gcc-4.3
> Reporter: Travis Vitek
> Fix For: 4.3
>
>
> I'm pretty confident that the following should compile and run without
> failure. It abbends with SIGABRT with recent versions of gcc-4.3.
> {noformat}
> $ cat t.cpp && g++ t.cpp && ./a.out
> #include <assert.h>
> struct empty_t
> {
> };
> struct trivial_t
> {
> long value;
> };
> template <class T>
> struct public_derived_t : T
> {
> };
> int main ()
> {
> assert (__is_pod(trivial_t));
> assert (__is_pod(public_derived_t<trivial_t>));
> assert (__is_pod(empty_t));
> assert (__is_pod(public_derived_t<empty_t>));
> return 0;
> }
> a.out: t.cpp:20: int main(): Assertion
> `__is_pod(public_derived_t<trivial_t>)' failed.
> Aborted
> {noformat}
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
