Mixing Laguages

Intel_C_Intel · ‎04-02-2004

Cananyonegiveme a thorough example of Fortran and C mixing including the commands for compiling/linking? I want Fortran to call C functions/subroutines. I followed the example on the manual and DOES NOT work. I have Intel Fortran 7.1 running on Win 2000. Thanks in advance.

This is what I have done:

Fortran Code:

PROGRAM test

REAL X, Y

EXTERNAL pointer_by2

X = 10

CALL pointer_by2(X,Y)

WRITE(*,*) X, Y

END

C Code:

#include
#include

void pointer_by2_(const float *input,float *output)
{
*output=*input * 2.0;
}

Using a C compiler I have make an object file from the C Code example. Then, I have used the following command to link:

ifl -o myprog f_code.for c_code.o

I get the following error:

Intel Fortran Compiler for 32-bit applications, Version 7.1 Build 20030307Z

Copyright (C) 1985-2003 Intel Corporation. All rights reserved.
ifl: Command line warning: unrecognized source type 'p_test.o'; object file assu
med

EPC Fortran-95 Version F95 Intel:200200:131124
Copyright (c) 1993-2000 EPCL. All Rights Reserved.
test_2.f90
program TEST

-out:myprog.exe
test_2.obj
p_test.o
p_test.o : warning LNK4078: multiple ".comment" sections found with different at
tributes (00000200)
test_2.obj : error LNK2001: unresolved external symbol _POINTER_BY2
myprog.exe : fatal error LNK1120: 1 unresolved externals

HELP!

TimP · ‎04-02-2004

You have followed the instructions for linux. The Windows compiler sets the link symbols to upper case by default, with no appended underscore. You should be OK if the C function is named POINTER_BY2().

I'm not sure which Windows C compiler would like to make a .o file rather than .obj, other than gcc, and I'm not sure that IFL will recognize -o. There is no supported compatibility between gcc and Intel compilers on Windows, but this may work.

Intel_C_Intel · ‎04-02-2004

I tried changing from lowercase to uppercase, appending an underscore or removing the underscore, but it doesn't work. Can youcompile/link my two simple code examples and tell me if they work? If they work, can you email me the object file of the C example.

Thank you in advance.