how to call C (non-intel C compiler) from ifort (intel fortran)? - Fortran

ktrchang@gmail.com wrote:
> Hi there,
>
> I need to call C within fortran code. I could compile and link using
> Visual Fortran
> and Visual C++.
>

> What is the right way to do?

There are plenty of examples in the doc directory of your Fortran
installation, including (if you have a current ifort) documents on the
ISO C interoperability scheme of current standard Fortran.

ktrchang@gmail.com wrote:

> I need to call C within fortran code. I could compile and link using
> Visual Fortran and Visual C++.

> CALL SUB1(arg1, .......)

> C code is like:
> #define sub1 __stdcall SUB1
> void sub1 ( arg1, ........)

> Now I have to use another machine with Intel Fortran (ifort)
> with .NET (Visual Studio 2005). When I linked, I got error message
> "unresolved external symbol _SUB1".

It is not unusual for Fortran subroutine and function names to
be generated with an extra _ on them. Also, since C is case sensitive
and the routine in the message is upper case change the C routine
name to _SUB1.

#define sub1 __stdcall _SUB1

-- glen

ktrchang@gmail.com wrote:
| Hi there,
|
| I need to call C within fortran code. I could compile and link using
| Visual Fortran
| and Visual C++.
|
| Fortran code is like:
| .
| CALL SUB1(arg1, .......)
| .
| .
| C code is like:
| #define sub1 __stdcall SUB1
| .
| void sub1 ( arg1, ........)
| .
| .
| Now I have to use another machine with Intel Fortran (ifort) with .NET
| (Visual Studio
| 2005). When I linked, I got error message "unresolved external symbol
| _SUB1".
| What is the right way to do? (For using ifort with icc, an example is
| shown in
|
http://www.ncsa.uiuc.edu/UserInfo/Re...trancallc.html)
|
| Any help is very much appreciated.

Intel changed the default calling convention from __stdcall to __cdecl,
when it took over the CVF. So, either adjust it on C side, or change the
calling convention on Fortran side. In addition, the way how CHARACTER
arguments are passed is also changed -- the hidden length is now passed
at the end of argument-list rather than immediately following the string
argument.

--
Jugoslav
___________
www.xeffort.com

Please reply to the newsgroup.
You can find my real e-mail on my home page above.

On Sep 27, 7:02 pm, ktrch...@gmail.com wrote:
> Hi there,
>
> I need to call C within fortran code. I could compile and link using
> Visual Fortran
> and Visual C++.
>
> Fortran code is like:
> .
> CALL SUB1(arg1, .......)
> .
> .
> C code is like:
> #define sub1 __stdcall SUB1
> .
> void sub1 ( arg1, ........)
> .
> .
> Now I have to use another machine with Intel Fortran (ifort) with .NET
> (Visual Studio
> 2005). When I linked, I got error message "unresolved external symbol
> _SUB1".
> What is the right way to do? (For using ifort with icc, an example is
> shown inhttp://www.ncsa.uiuc.edu/UserInfo/Resources/Hardware/Intel64Cluster/D...)
>
> Any help is very much appreciated.


Thank you all for the postings.

In ifort /help, it shows:
/Gm enable CVF and Powerstation calling convention
compatibility
(same as /iface:cvf)

With /Gm, error of unresolved external symbol is resolved.

BTW, I intended to include link below but it was cut off.
http://www.ncsa.uiuc.edu/UserInfo/Re...ntel64Cluster/
Doc/fortrancallc.html

ReggieC