Add modpython to ZNC port

[Feuermurmel (Michael Schwarz)]

I tried to add modpython (by specifying --mod-python to configure) to the ZNC port as a variant but failed because of multiple problems. The attached diff is how far I got.

Simply adding the necessary arguments and environment variables for configure leads to a compiler error in modpython/_znc_core.cpp along those lines:

modpython/_znc_core.cpp:21058:11: error: no matching member function for call to 'erase'
  (arg1)->erase(arg2);
  ~~~~~~~~^~~~~

Not having a lot of experience with C++ and not finding any reference to this specific error when compiling ZNC online, I tried building ZNC with g++ instead of clang. This worked but if I try to do this by setting compiler in the Portfile (as can be seen in the patch), configure fails because of some problem with Perl:

checking for perl... /opt/local/bin/perl
checking for perl_alloc in -lperl... no
configure: error: perl not found. Try --disable-perl.

I would really like to see support modpython in the ZNC port but I don't think I can get this to work myself.

[mf2k (Frank Schima)]

This variant should be called python33 instead to reflect the python version. Also, why does it set the compiler to gcc48?

[Feuermurmel (Michael Schwarz)]

I agree to your comment about the variant's name. Setting the compiler to gcc-4.8 is a leftover from my attempt to get the port to compile at all with modpython enabled. It seems that clang doesn't like some code in the generated SWIG bindings but I sure hope that switching to GCC isn't actually necessary to enable this variant.

[mf2k (Frank Schima)]

Setting configure.compiler directly is not how we handle that now. Instead, you can use blacklist to blacklist compilers.

[Feuermurmel (Michael Schwarz)]

I've updated the patch to use compiler.blacklist and also added a variant for Python 3.4. I still hope that this can be done without blacklisting Clang.

[mfeiri]

Applied in r123377 with small modifications. clang-503.0.40 can successfuly compile modpython, so I limited the scope of the blacklist. Thanks for this patch!