How to Instruct mingw64-gcc to use Specific mingw-w64-headers/crt

I have compiled mingw-w64-headers and mingw-w64-crt as described here.My issue is how to get gcc to use them.

I have tried the following to no avail:

SET mingw_dir=C:\msys64\mingw-w64gcc -g -L %mingw_dir%\lib^    -I %mingw_dir%\include^    -Wl,--rpath=%mingw_dir%\lib^    test.c -o test

It fails to compile giving:

../lib/crt2.o: in function 'pre_c_init':crt/crtexe.c:145: undefined reference to '__p__commode'

This seems to be an issue with ld, however I'm not sure how to solve it.