> > [jh@gcc2-power8 gcc]$ cat ../b.f90
> > ! This testcase will abort if C_CHAR types are not interoperable
> > module lto_type_merge_test
> > use, intrinsic :: iso_c_binding
> > implicit none
> >
> > contains
> > function types_test1(V) bind(c)
> > USE, INTRINSIC :: ISO_C_BINDING
> > CHARACTER(C_CHAR) :: types_test1
> > CHARACTER(C_CHAR), VALUE :: V
> > types_test1 = V
> > end function types_test1
> > end module lto_type_merge_test
> >
> > [jh@gcc2-power8 gcc]$ cat ../a.c
> > extern unsigned char types_test1 (char v);
> > void
> > main ()
> > {
> > if (types_test1 ('a') != 'a')
> > __builtin_abort ();
> > return 0;
> > }
> >
> > As my fortran-fu goes, i think this testcase is correct. Fortran FE however
> > builds types_test1 as a function return char but taking the array of size
> > of 1
> > as a parameter.
> C_CHAR is a named constant of value 1 (the number of bytes of a char),
> and character(foo) declares a string of length foo and default kind
> (which is 1 for character types).
> So it is expected that the argument is an array.
I see, what is the reason for assymetry for return value to not be array in
this case?
> If you want to declare a single character, you have to use an integer of
> kind 1.
> types_test1's result and v should have type integer(c_char), I think.
I will fix the testcase accordingly. I basicallly copied what is in table
15.2 of the Fortran 2008 draft that explicitely lists Fortran type CHARACTER
if kind C_CHAR compatible with "char". On the other hand there are no examples
in the standard that would suggest that this should work this way.
It only shows stuff like
CHARACTER(KIND=C_CHAR), DIMENSION(*) :: IN, OUT
which corresponds to char []
Is my testcase supposed to work if I simply add KIND= before "C_CHAR"
If you can look at the other c-bind testcases I produced, I would really
appreachiate that.
Honza
>
> Mikael
