Invalid C++ or bug in GCC 4.8

From:

marcel.loose@googlemail.com

Newsgroups:

comp.lang.c++.moderated

Date:

Wed, 26 Jun 2013 18:46:37 CST

Message-ID:

<074b0c36-6687-44c6-9d21-d797f573e507@googlegroups.com>

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Hi all,

I was quite unhappy to find out that code I've written years ago suddenly
fails to compile with the latest GCC (4.8). It compiles without warning
(with -Wall and -Wextra) with GCC 4.7.3 as well as with Clang 3.2.

Below is a completely stripped down version of the code. Is this illegal
C++ code, or is this a bug in GCC 4.8?

<code>
template <typename Signature, typename TypeId> class ObjectFactory;

template<typename Base , typename TypeId>
class ObjectFactory<Base (), TypeId> { };

struct Abstract { virtual ~Abstract() = 0; };

struct Concrete : Abstract { };

typedef ObjectFactory< Abstract(), int> MyFactory;
</code>

When compiling with GCC 4.8 I get the following error:

Eabstract-class-type.cc:10:33: error: ?type name? declared as function returning an abstract class type
typedef ObjectFactory< Abstract(), int> MyFactory;
                                 ^

Marcel Loose
Senior Software Engineer
Computing Group, Research & Development
ASTRON

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