C++
Starting with version 3, REDHAWK is compiled at C++ 14.
Redhat/CentOS has Devtoolset to allow a host to have multiple C++ toolchains installed. See the section 'Development Tools Setup' for scripts distributed with REDHAWK to help switch between these toolchains.
Older components are not necessary incompatible from a C++ ABI perspective. To understand that aspect of compatibility, see the next section.
C++ Language Standard Support
To ensure compatibility, it is important that your compiler has complete support for your C++ language standard. For example, g++ version 4.x.x has complete support for C++98/C++03, while g++ version 5.x.x has complete support for C++11. If object A was compiled with g++ 4.8.5 at -std=gnu++03 and object B was compiled with g++ 5.1.0 at -std=gnu++11, then these objects are ABI compatible and can be linked.
As a counter-example, g++ version 4.x.x does not have complete support for C++11. If object A was compiled with g++ 4.8.5 at -std=gnu++11 and object B was compiled with g++ 5.1.0 at -std=gnu++11, then these objects are ABI incompatible and should not be linked.
To determine whether a version of g++ has complete support for a language standard, look here.
REDHAWK is developed and tested using the C++14 standard and may not compile in C++17 or newer modes. To configure GCC to use the C++14 standard, set the CXXFLAGS environment variable before building REDHAWK from source:
export CXXFLAGS="--std=gnu++14"Development Tools Setup
REDHAWK supports CentOS 7, for which the default C++ compiler is g++ version 4.x.x, with complete support for C++98/C++03, but not for later versions. REDHAWK requires a compiler with complete support for the C++14 standard. For CentOS 7, that is provided by Software Collections (SCL), in the devtoolset-<ver>-gcc-c++ rpm package.
The devtoolset-<ver>-gcc-c++ rpm package installs to the /opt/ directory a set of GNU software development tools such as g++, gdb, ld, and autoconf. The use of these tools is enabled by prepending several environment PATH-like variables with /opt/rh/devtoolset-<ver>. After completing the ./redhawk-install.sh command below, these commands will be available to enable and disable them:
. $OSSIEHOME/bin/redhawk-devtoolset-enable.sh
. $OSSIEHOME/bin/redhawk-devtoolset-disable.shIf you want these tools enabled automatically, add redhawk-devtoolset-enable.sh to ~/.bashrc, or similar.