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gccfortrangfortrangcc-warning

Which gfortran compiler flag is associated with the warning "Illegal preprocessor directive"?

When using pFUnit (3.2.9) to test my Fortran code, I get many "Illegal preprocessor directive" warnings, e.g.

Warning: Illegal preprocessor directive
/path/to/my/file/test.f90:37:2:

 #line 26 "/path/to/my/file/test.f90"
  1

The code compiles and runs fine, so I would like to turn off these warnings, while still seeing other compiler warnings. Which gfortran compiler flag turns this specific warning off? I am working with gfortran 7.3.1.

Solution

  • This is not the kind of warning that one should turn off because not using a preprocessor has usually very bad consequences on codes that use the most common directives like #define and #if. And as far as I know it isn't possible to turn it off.

    It is much wiser to enable the preprocessor using the -cpp flag. Not only the warnings will stop but you will get the correct line numbers in further diagnostics as well, the line numbers will refer to your original code.