Dear Mojtaba,
Please note that this list is devoted to the development of gfortran;
go to the likes of comp.lang.fortran for help with the language
itself. Better still read the book or google "C fortran
interoperability". That said, this works:
(Note well the arguments in the prototype for 'multab' and the
provision of a C binding name in the fortran. Also, uppercase is
traditional for fortran but is by no means obligatory - )
it is simply ignored.)
#include <iostream>
using namespace std;
extern "C" int multab(int *a, int *b);
int main()
{
int a=3, b=8;
while (a > 0 && b > 0)
{
cout << "please input a and b" << endl;
cin >> a >> b;
cout << "a * b = " << multab(&a, &b) << endl;
}
return 0;
}
function multab(a, b) bind(c, name = "multab")
use iso_c_binding
implicit none
integer(c_int), intent(in), bind(c) :: a, b
integer(c_int) :: multab
multab = a * b
end function multab
pault@paul-laptop:/tmp# g++ main.cpp FSub.f90
pault@paul-laptop:/tmp# ./a.out
please input a and b
2 2
a * b = 4
please input a and b
Good luck
Paul
On Wed, Jan 11, 2012 at 8:33 AM, Mojtaba Seifi <mojtaba.seifi@xxxxxxxxx> wrote:
> Dear Sir/Madam,
>
> I'm trying to compile a simple fortran code using gfortran and then using
> this library in a C++ code (compiling by g++). The simple codes for fortran
> and C++ are attached. I use the following commands in terminal (ubuntu) for
> this purpose:
>
> gfortran -c FSub.f90
> ar -rcs libFsub.a FSub.o
> g++ -c main.cpp
> g++ -o main.exe main.o -L/`pwd` -lFsub
>
>
> But I get the following error:
> --------------
> main.o: In function `main':
> main.cpp:(.text+0x41): undefined reference to `MULTAB_'
> collect2: ld returned 1 exit status
> --------------
> I couldn't find any solution on the Internet for this issue.
> Would you please help me on this. I'm new in linux and have no idea how to
> fix this.
>
> Thank you.
>
> --
> Mojtaba
>
--
The knack of flying is learning how to throw yourself at the ground and miss.
--Hitchhikers Guide to the Galaxy
