[Discuss-gnuradio] GNURadio/Module builds and std=C++11

[Ghost Op]

Hi everyone,

I've run into this on every Ubuntu 16.04 box I've installed gnuradio
and OOT modules on and Google doesn't seem to have a nice clean answer
(the search answer is always add a compile flag) so I figured I'd ask
the group.

When I build modules (gr-osmosdr in particular with libfreesrp support
I run into this) on a fresh Ubuntu 16.04.2 LTS install, I run into a
warning like this: "warning: non-static data member initializers only
available with -std=c++11 or -std=gnu++11".  Depending on the code it
may produce errors on some lines preventing compilation.

I know what causes it, the compiler is defaulting to something earlier
than the  c++11 standard (like C++99) with the Ubuntu repo gcc version
(5.4) installed, so some of the syntax in the code is causing the
warning.  I can modify the CMake and add this to it "set
(CMAKE_CXX_STANDARD 11)" and it builds after that, but my guess is
that this builds on everyone else's Ubuntu without these modifications
or the setting would be standard in the CMake files.  What I'd really
like to do is tell the compiler to default to -std=C++11 even if it's
not explicitly provided as a compile flag, but again if everyone were
running into it I think it would have been fixed another way.

If I do the same build on a standard debian build with gcc 6.3 it
builds clean so it's definitely a default standard issue for compilers
on Ubuntu 16.04.

Does anyone have any insight/suggestions?

Thanks!