https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64138
kargl at gcc dot gnu.org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |WAITING
Last reconfirmed| |2014-12-01
Ever confirmed|0 |1
--- Comment #4 from kargl at gcc dot gnu.org ---
(In reply to kargl from comment #1)
> (In reply to david from comment #0)
> > Hi,
> >
> > I have created a complex number module:
> >
> > module complex_number_module
> > implicit none
> >
> > integer, parameter :: loc_real_precision = 8
> >
> > type complex_number
> > real(kind=loc_real_precision) :: real_part, imag_part
> > end type complex_number
> >
> > interface c_sub
> > module procedure c_sub_cc, & ! z1 - z2
> > c_sub_cr, & ! z1 - num, where num is a
> > real number
> > c_sub_rc ! num - z1, where num is a
> > real number
> > end interface
> >
> > ! --------------------------------------------------------------------------
> > type (complex_number) function c_sub_cc (z1, z2)
> >
> > type (complex_number), intent(in) :: z1, z2
> >
> > c_sub_cc%real_part = z1%real_part - z2%real_part
> > c_sub_cc%imag_part = z1%imag_part - z2%imag_part
> >
> > end function c_sub_ccj
> >
> > ! --------------------------------------------------------------------------
> > type (complex_number) function c_sub_cr (z1, num)
> >
> > type (complex_number), intent(in) :: z1
> > real(kind=loc_real_precision), intent(in) :: num
> >
> > c_sub_cr%real_part = z1%real_part - num
> > c_sub_cr%imag_part = z1%imag_part
> >
> > end function c_sub_cr
> >
> > ! --------------------------------------------------------------------------
> > type (complex_number) function c_sub_rc (num, z1)
> >
> > type (complex_number), intent(in) :: z1
> > real(kind=loc_real_precision), intent(in) :: num
> >
> > c_sub_rc%real_part = num - z1%real_part
> > c_sub_rc%imag_part = - z1%imag_part
> >
> > end function c_sub_rc
> >
> > end module complex_number_module
> >
> > When I compile with gfortran (version 4.6.4), I got the following error:
> >
> > module_twoway_rrtmg_aero_optical_util.F:14.85:
> >
> > c_sub_rc ! num - z1, where num is a real number
> > 1
> >
> > Error: Ambiguous interfaces 'c_sub_rc' and 'c_sub_cr' in generic interface
> > 'c_sub' at (1)
> >
> > I don't see any ambiguity and I don't encounter any problem with other
> > compilers such pgi and ifort. Please advise.
> >
> > Cheers,
> > David
>
> Please attach the exact code you tried to compile. The above is nonsense.
I fixed the above code. I believe gfortran is correct to complain
about an ambiguous interface. In the last two line below, which
of c_sub_rc and c_sub_cr should be called.
program foo
use complex_number_module
type(complex_number) a, b
real(dp) x
a%re = 1
a%im = 2
x = 1
b = c_sub(a, x); print '(A,2F5.1)', 'a-x = ', b%re, b%im
b = c_sub(x, a); print '(A,2F5.1)', 'x-a = ', b%re, b%im
b = c_sub(z1=a, num=x); print '(A,2F5.1)', 'a-x = ', b%re, b%im
b = c_sub(num=x,a); print '(A,2F5.1)', 'a-x = ', b%re, b%im
end program foo
