Using gnulib with -pedantic, I get many warnings about #include_next

[Reuben Thomas]

I compile my code with -pedantic, because I want it to work with compilers 
other than GCC. This means that my compiler output is littered with warnings 
about #include_next. How can I stop this? It's a pain to read through; of 
course I can grep out the warnings, but that's that's an annoyance too, as I 
have to remember to do this everywhere (shell, emacs &c.).

Is there some way for gnulib to stop gcc giving me these warnings? Of 
course, if I use #include_next in my own code, I want to be warned about it, 
as I shouldn't be using it, but gnulib is, I presume, only using 
#include_next if it has already detected that it's being used under gcc.