https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65969
Bug ID: 65969
Summary: typename allowed in using declaration of non-types
names
Product: gcc
Version: 5.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: bitte.keine.werbung.einwerfen at googlemail dot com
Target Milestone: ---
Created attachment 35438
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35438&action=edit
various cases of using declarations of non-types
The standard draft states for using declarations in 7.3.3/19:
---
If a using-declaration uses the keyword typename and specifies a dependent name
(14.6.2), the name introduced by the using-declaration is treated as a
typedef-name
---
However, if the 'nested-name-specifier unqualified-id' names a non-type, a
typedef on this name would be invalid. Nevertheless, g++-5.1 issues no error
for the following code snippet:
<<< SNIP
template < typename T >
class BaseTemplate {
protected:
T member;
};
template < typename T >
struct SubTypename : protected BaseTemplate< T > {
using typename BaseTemplate< T >::member; // clang and icpc fail here
};
>>> SNAP
More related cases are in the attached file. The standard is not 100% concise
about the usage of typename in using declarations. However, clang and icpc both
complain about misplaced typenames. What do the experts think?
related: 55664
I wrote on stackoverflow, but I'm actually unsure if I'm really right:
http://stackoverflow.com/questions/25944000/c-using-declaration-with-typename-in-inheriting-constructors/29965088#29965088
