This is the mail archive of the
gcc-help@gcc.gnu.org
mailing list for the GCC project.
Re: Preprocess files with gcc/gfortran vs. cpp
- From: Tim Prince <n8tm at aol dot com>
- To: gcc-help at gcc dot gnu dot org
- Date: Fri, 19 Feb 2016 15:22:39 -0500
- Subject: Re: Preprocess files with gcc/gfortran vs. cpp
- Authentication-results: sourceware.org; auth=none
- References: <CAAbhqc4XhDdXUDQAoX6_5ZO6vcsEcHBha0dkydT034oPrWa-OQ at mail dot gmail dot com> <CAAbhqc4XazRxu7rCQED+66yT1XOXke3axDS2=g7aNcqpVgzx1g at mail dot gmail dot com> <CAH6eHdRwCFU8G3m3rOu-UWuxWNVr-tcePgW4Msu1QP_U0pK4Zw at mail dot gmail dot com>
- Reply-to: tprince at computer dot org
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?
--
Tim Prince