Preprocess files with gcc/gfortran vs. cpp

[Jonathan Wakely]

On 19 February 2016 at 20:22, Tim Prince wrote:
>
>
> On 2/19/2016 2:30 PM, Jonathan Wakely wrote:
>> On 19 February 2016 at 19:01, Nick Papior wrote:
>>> Am I missing some point here?
>>> I would have expected gcc/gfortran to use the _same_ preprocessing
>>> utility as that provided in cpp?
>> By default cpp works in C mode, but when invoked by the Fortran
>> front-end it runs in a different mode. If you use cpp -x f97-cpp-input
>> then it works in F95 mode, and you get results consistent with
>> invoking gcc on a .f file, or invoking gfortran.
>>
>> I don't know why cpp treats C and Fortran input differently, but
>> that's why you don't see what you expect.
> The most obvious reason is that C99/c++ style pre-processing will break
> the Fortran // operator (introduced in f77). It doesn't make sense if
> the previous -traditional option for gcc was changed to f97-cpp-input.
> Did you mean something like f77-cpp-input?

Oops, yes, I meant -f95-cpp-input