https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97031
--- Comment #5 from jean-pierre.flam...@univ-lille.fr ---
I am sorry to bother you once again, for the last time. I have now understood
all things that happened while compiling the very complicated (!) program
below.
========================
program tstmak
implicit none
! a comment with /*
integer :: i
!
#ifdef _MYDEBUG_
print *,' debug printing'
#endif
i = 25
print *,'normal printing: i=',i
end program tstmak
========================================
I compiled this fortran with and without -cpp, and always with -D_MYDEBUG_ in a
command like that one
gfortran -v -ffree-form -Wall -msse2 -g -fbounds-check -fbacktrace -D_MYDEBUG_
-cpp tstmak1.f -o v1
1) if -cpp is PRESENT
a) the '/*' in the comment line causes a great problem (in that case an "end
of file") and no executable is produced
b) if I change the '/*' to anything else, no message, the executable is
produced, and prints what is expected
2) if -cpp is ABSENT
a) the '/*' in the comment line has no catastrophic effect, but a WARNING
appears
"Warning: tstmak.f:6: Illegal preprocessor directive"
however the executable is produced, and prints what is expected
It is because of this warning (and not an error) that I always put "-cpp" in my
makefiles !
===> conclusion: gfortran "tolerates" and understands "#" type directives.
This is in opposition to other compilers, which also caused my trouble
Sorry for the disturbance
JP Flament
----- Mail original -----
De: "kargl at gcc dot gnu.org" <gcc-bugzi...@gcc.gnu.org>
À: "jean-pierre flament" <jean-pierre.flam...@univ-lille.fr>
Envoyé: Dimanche 13 Septembre 2020 11:55:28
Objet: [Bug fortran/97031] the content of a comment line breaks compilation
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97031
--- Comment #3 from Steve Kargl <sgk at troutmask dot apl.washington.edu> ---
On Sun, Sep 13, 2020 at 08:02:01AM +0000, jean-pierre.flam...@univ-lille.fr
wrote:
>
> I just noticed that cpp recognizes the extensions .fpp .F and other uppercase
> extensions.
> This is why I added -cpp in the gfortran command (otherwise I have a
> diagnostic
> because of #ifdef's
>
> I have renamed my file with the .fpp extension; with "-cpp" in the gfortran
> submission I get the same errors.
>
> If I compile the file with extension *.f or .fpp without -cpp
>
> 1) the compilation has no error
> 2) a #ifdef...#endif is recognized even with a .f extension, without -cpp, in
> my simple example, (I should check that the directive really is taken into
> account !)
> 3) IF I compile my full project in a makefile, the absence of "-cpp" in the
> gfortran command induces
> a "Illegal preprocessor directive" error in all the routines having that
> #ifdef...#endif
>
I don't quite follow you. But, it come down to gfortran uses
the C pre-processor when asked to pre-process a file. If you
have a C language construct such as '/*' in your Fortran code
it will cause problems.
