clang 7.0 support - individual warning levels

[gabyx]

this not a really good pull request, I started it, to keep working on these c++17 warnings...

• there are two warnings regarding array bound checks somewhere in the catch.hpp dependency (think its marco expansion?)

/Users/gabrielnuetzi/Desktop/rttr/src/rttr/../rttr/detail/impl/array_range_impl.h: In function 'void ____C_A_T_C_H____T_E_S_T____139()':
/Users/gabrielnuetzi/Desktop/rttr/src/rttr/../rttr/detail/impl/array_range_impl.h:200:105: warning: array subscript is below array bounds [-Warray-bounds]
     return (empty_() ? const_reverse_iterator{m_begin, this} : const_reverse_iterator{m_begin - 1, this});

• lots of no-except warnings:

/Users/gabrielnuetzi/Desktop/rttr/src/rttr/../rttr/detail/registration/registration_impl.h:205:60: error: mangled name for 'rttr::registration::bind<rttr::detail::meth, Class_Type, F, acc_level> rttr::registration::class_<Class_Type>::method(rttr::string_view, F, acc_level) [with F = long unsigned int (std::__cxx11::basic_string<char>::*)() const noexcept; acc_level = rttr::detail::public_access; Class_Type = std::__cxx11::basic_string<char>]' will change in C++17 because the exception specification is part of a function type [-Werror=noexcept-type]
 registration::bind<detail::meth, Class_Type, F, acc_level> registration::class_<Class_Type>::method(string_view name, F f, acc_level level)

[acki-m]

You should merge my pullrequest changes into yours. So we can see whether the compile errors are gone.
I think it is better you find a solution, where the warnings are gone, without removing werror.
What do you think?

[coveralls]

Coverage increased (+0.1%) to 90.235% when pulling d0e9083 on gabyx:disable-warnings into 29e6ff9 on rttrorg:master.

[gabyx]

jeah of course!! :-) but I have not so much time fixing these now (also I am not really experienced in these errors...), but of course one should fix them (maybe you could point out some places to look at or how to potentially fix them?)
I just made a branch to build without -Werror... such that it compiles...

to be continued...

[acki-m]

The thing is, when somebody is using RTTR and he likes to user -Wall and -Werror, he cannot use RTTR.
because he will get compile errors, because the problematic code are in the class templates.

So your changes will not help here. You have to find a way to correctly fix the code or disable the warning directly in the header files.
When you can provide enough info to me, that we cannot fix the code and have to disable the warning, then I would merge your PR.

[gabyx]

Thats true, my fix is only a stupid hack at the moment...

[acki-m]

@gabyx
I will merge this now.
thx

[gabyx]

thx too for your efforts