https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91119
Bug ID: 91119
Summary: Bogus type re-difinition error
Product: gcc
Version: 9.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: me at adhokshajmishraonline dot in
Target Milestone: ---
Test code
---------
class A {};
class B {
using C = A;
enum D {
A,
};
};
When the above code is compiled using g++ (g++ -c test.cpp -o test.o), the
compiler produces the following output:
╭─ adhokshajmishra@andromeda in /tmp
╰─➤ g++ -c test.cpp -o test.o
test.cpp:7:9: error: declaration of ‘A’ changes meaning of ‘A’ [-fpermissive]
7 | A,
| ^
test.cpp:1:7: note: ‘A’ declared here as ‘class A’
1 | class A {};
| ^
If the same code is compiled with clang, there is no error produced. The
following workaround seems to work:
class A {};
class B {
using C = ::A;
enum D {
A,
};
};
As far as I know, original test code is correct as per C++11 standard:
<quote>
A class name (9.1) or enumeration name (7.2) can be hidden by the name of a
variable, data member, function, or enumerator declared in the same scope. If a
class or enumeration name and a variable, data member, function, or enumerator
are declared in the same scope (in any order) with the same name, the class or
enumeration name is hidden wherever the variable, data member, function, or
enumerator name is visible.
</quote>
