Experimental Physics and
Industrial Control System

Dirk Zimoch <[email protected]> · Fri, 24 Nov 2017 10:48:49 +0100

I don't know how to fix this.

I cannot make ClientProvider::Impl a friend because it is not yet known

when ClientChannel declares it is friends.

I cannot put ClientProvider in front of ClientChannel because it uses

members of ClientChannel which will then be unknown.

On 24.11.2017 10:41, Dirk Zimoch wrote:

On 24.11.2017 08:38, Dirk Zimoch wrote:

vxWorks 6.3 fails with:

In file included from ../../src/client/client.cpp:15:
../../src/client/pv/pvAccess.h:1363: warning: `class
epics::pvAccess::ChannelProviderRegistry' has virtual functions but
non-virtual destructor
../../src/client/client.cpp:30: error: `struct
pvac::ClientChannel::Impl' is private
../../src/client/client.cpp:163: error: within this context
make[4]: *** [client.o] Error 1

gcc 3.4.4 probably follows this logic:

class epicsShareClass ClientChannel
{
    struct Impl;
    std::tr1::shared_ptr<Impl> impl;
    friend class ClientProvider;

ClientChannel::Impl is a private type of ClientChannel and
ClientProvider is a friend.

struct ClientProvider::Impl
{
    pva::ChannelProvider::shared_pointer provider;

    epicsMutex mutex;
    typedef std::map<std::pair<std::string, ClientChannel::Options>,
std::tr1::weak_ptr<ClientChannel::Impl> > channels_t;
    channels_t channels;
};

ClientProvider::Impl is not a friend of ClientChannel thus it cannot use
the private ClientChannel::Impl.

It seems other compiler versions have a broader understanding of
friendship than this one.

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System