[CMake] Fortran project compiling with -isystem causing error

[Hugh Sorby]

Hi All,

I am trying to create a simple Fortran project that relies on a module 
file that has been built by another project.  I have added the directory 
containing the module file into the include_directories command but the 
project isn't compiling and raises an error can't find module.  The 
directory that I want to include shows up in the compile command but it 
is prefixed with -isystem if I change this manually to -I (capital i) 
then the project compiles successfully.  As I understand it the -isystem 
should be used for includes to be considered as system includes, but I 
haven't specified this in my include_directories command.

I don't understand what is going on I am expecting to see -I 
/path/to/my/module and not -isystem /path/to/my/module.

Any help is appreciated,

Cheers,
Hugh.