Re: Compiler problem with gfortran

[Jonathan Wakely <jwakely.gcc@gmail.com>]

On Sun, 24 Apr 2022, 17:59 C. David Whiteman via Gcc-help, <
gcc-help@gcc.gnu.org> wrote:

> Am having some trouble compiling a simple fortran program on my M1 MacBook
> Air. I am using the latest MacOS, Monterey 12.3.1, and the latest version
> of Xcode. I installed Homebrew and gcc to update my old version of
> gfortran. The fortran program on my desktop will compile when I use the
> command gfortran -c skippy.f, producing the executable file skippy.o


That's not an executable file, it's an object file. You used the -c option
which says to stop after compilation and not link the object into an
executable.

If you remove the -c option you'll get an executable.




on my desktop. But I can’t get the executable file to run. I am an amateur
> and am really not that familiar with the unix commands, etc. Can someone
> give me some advice on this? Thanks.
>
> -Dave
>
> ~/Desktop 519 $ gfortran -o skippy.f
> gfortran: fatal error: no input files; unwilling to write output files
> compilation terminated.
> ~/Desktop 520 $ gfortran -c skippy.f
> ~/Desktop 521 $ ./skippy.o
> -bash: ./skippy.o: Permission denied
> ~/Desktop 522 $ gfortran skippy.f
> ld: library not found for -lSystem
> collect2: error: ld returned 1 exit status
> ~/Desktop 523 $ g77 skippy.f
> -bash: g77: command not found
> ~/Desktop 524 $