* -Wsuggest-override is not supported by gcc before 5.0
* GCC prior to 5.0 should ignore not only -Wnon-virtual-dtor but also -Weffc++, otherwise non-virtual destructor problems will still be reported.
* The `#pragma GCC diagnostic push' should be used before setting up the temporary environment.
* When using GCC4.8, use manual lexical analysis instead of regular expressions.
* Add gcc4.8 stuff to travis file.
Here is the warning currently being produced:
CMake Warning (dev) at C:/Program Files/CMake/share/cmake-3.19/Modules/GNUInstallDirs.cmake:223 (message):
Unable to determine default CMAKE_INSTALL_LIBDIR directory because no
target architecture is known. Please enable at least one language before
including GNUInstallDirs.
Call Stack (most recent call first):
I noted how I fixed the error. This is caused by GNUInstallDirs automatically executing code just by including it.
I also added -Werror=dev to the CI to ensure this never happens again.
Co-authored-by: Juan Ramos <juanr0911@gmail.com>
It appears that the `libc++` available on Ubuntu 14.04 is broken and
doesn't handle the boolean regex correctly. Newer versions appear to be
correct but I have to work out how to get 14.04 to use it.
