------- Additional Comments From sgk at troutmask dot apl dot washington dot
edu 2005-08-06 16:03 -------
Subject: Re: gfortran .f90 complex parameter initialization syntax bug
On Sat, Aug 06, 2005 at 03:02:37PM -0000, christopherbuell at mindspring dot
com wrote:
>
> (In reply to comment #3)
>
> Got it. I don't know the F90 or F95 standard very well.
The Standard can be tricky to read. I have a draft of
F2003 here so I'll quote that
7.1.7 Initialization expression
An initialization expression is an expression with limitations that
make it suitable for use as a kind type parameter, initializer, or
named constant. It is an expression in which each operation is
intrinsic, and each primary is
(1) A constant or subobject of a constant,
(2)-(11) Don't apply.
real, parameter :: x = -1.e0 ! Uses a constant.
complex, parameter :: z = (1.e0, -1.e0) ! Uses constants.
complex, parameter :: c = (x,-x) ! x is a named constant, -x is not.
You probably found a vendor extension, because -x could be
evaluated at compile time.
If you really want to sit and puzzle over the standard. Consider
program c
real, parameter :: o = 1.e0
real, parameter :: t = 2.e0
real, parameter :: h = o / t ! This is ok.
complex, parameter :: z = (o / t, h) ! This is not ok.
print *, o, t, h
end program c
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23254
