https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71173
Bug ID: 71173
Summary: [6 regression] Qualified name lookup
Product: gcc
Version: 6.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: Casey at Carter dot net
Target Milestone: ---
This program should compile without error:
namespace foo {
namespace bar {
class foo {};
}
class baz {};
}
using namespace foo::bar;
::foo::baz mybaz;
but GCC 6 reports (http://melpon.org/wandbox/permlink/2n9QQUT0UIXog2Cj):
prog.cc:9:8: error: 'baz' in 'class foo::bar::foo' does not name a type
::foo::baz mybaz;
^~~
The name `::foo` should refer to the namespace `::foo`, not to the class
`::foo::bar::foo` per [namespace.qual]/2:
For a namespace X and name m, the namespace-qualified lookup set S(X,m) is
defined as follows: Let S0(X,m) be the set of all declarations of m in X and
the inline namespace set of X (7.3.1). If S0(X,m) is not empty, S(X,m) is
S0(X,m); otherwise, S(X,m) is the union of S(Ni,m) for all namespaces Ni
nominated by using-directives in X and its inline namespace set.
S0(::,foo) is not empty, so namespaces nominated by using-directives should
never be examined.
