• Brad King's avatar
    Fortran: Do not suppress explicit use of implicit include directories · 3dc81a48
    Brad King authored
    Since commit 2e91627d (ParseImplicitIncludeInfo: add Fortran implicit
    include handling, 2019-01-25, v3.14.0-rc1~73^2) we actually populate
    `CMAKE_Fortran_IMPLICIT_INCLUDE_DIRECTORIES` for the first time.  This
    value may be useful to project code to pass to other tooling that wants
    to preprocess the way Fortran does, so we should compute the value.
    However, compilers like `gfortran` do not actually search their own
    implicit include directories for `.mod` files.  The directories must be
    passed via `-I` in order for `.mod` files in them to be found.
    Since Fortran has no standard library header files that we need to avoid
    overriding, it is safe to *not* filter out implicit include directories
    from those passed explicitly via `-I` options.  Skip this filtering so
    that include directories specified by project code to find `.mod` files
    will be searched by the compiler even if they happen to be implicitly
    searched by the preprocessor.
    Fixes: #18914