https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109275
kargl at gcc dot gnu.org changed:
What |Removed |Added
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CC| |kargl at gcc dot gnu.org
--- Comment #1 from kargl at gcc dot gnu.org ---
(In reply to Raoul Hidalgo Charman from comment #0)
> The following example, where an interface is defined for the surrounding
> program unit fails to compile:
>
> function foo(arg1) result(res)
>
> interface foo
> function foo(arg1)
> integer*2 foo(3)
> integer*8 arg1
> end function foo
> end interface
>
> integer*2 res(3)
> integer*8 arg1
> res = (/1,2,int(arg1,4)/)
> end function
>
> Giving the error:
>
> recursive-interface.f:4:8:
>
> 4 | function foo(arg1)
> | 1
> Error: Procedure pointer result ‘foo’ at (1) is missing the pointer attribute
>
> Given you can use this function with that interface, this appears to be an
> incorrect warning.
It's not a warning. It is an error. And, yes it seems wrong.
>
> While I don't see any reason why a correctly defined interface would not be
> allowed, especially if it's not even used and result is used to disambiguate
> the symbol, other compilers do fail to compile and complain about using an
> interface with the same name as the surrounding program unit. XLF complained
> for normal interfaces, while Sun Studio just complains for generic interface.
>
> GFortrans error message should at least be more informative, explicitly
> saying it's not allowed if this is the case.
>
> I came across this issue because a library had an include with many
> interfaces, and was then trying to use some of those interfaces in the
> definitions of those program units.
It seems to be invalid Fortran. From Fortran 2018
C1501 (R1501) An interface-block in a subprogram shall not contain
an interface-body for a procedure defined by that subprogram.
It seems gfortran is missing a check for C1501.
