GFortran can’t find system headers

[Nikita Karetnikov]

I’m trying to package APL, which requires LAPACK, which requires
Fortran.

Here’s my attempt to add the last one:

(define-public gfortran-4.8
  (package (inherit gcc-4.8)
    (name "gfortran")
    (arguments `(#:configure-flags '("--enable-languages=fortran")))))

I get the following error while trying to build it:

The directory that should contain system headers does not exist:
  /usr/include

Note that GFortran inherits GCC 4.8, which has these lines:

      (native-search-paths
       (list (search-path-specification
              (variable "CPATH")
              (directories '("include")))
             (search-path-specification
              (variable "LIBRARY_PATH")
              (directories '("lib" "lib64")))))

Then why does the error appear?

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