nvcc Compiler problem in FORTRAN-C Mixed language programming
Under platform windows xp, Geforce 8800GT and Visual studio 2005
I want to access the Fortran module global variables in nvcc subroutines.(I use Intel fortran 10.1.019 compiler).
As Intel fortran compiler’s document says,
modules are the simplest way to exchange large groups of variables with C, because Intel Fortran modules are directly accessible from C/C++.
The following example declares a module in Fortran, then accesses its data from C:
//—File ctest.c—
[codebox]
extern void SET_DATA(void)
{
extern int HOST_DATA_mp_A;
HOST_DATA_mp_A=10;
return;
}
[/codebox]
C—File ftest.for—
[codebox]
MODULE HOST_DATA
IMPLICIT NONE
INTEGER A
END MODULE
PROGRAM TEST
USE HOST_DATA
IMPLICIT NONE
CALL SET_DATA
PRINT*,‘A=’,A
STOP
END
[/codebox]
I first use nvcc compiler compile ctest.c to object file
nvcc -c ctest.c
This will generate ctest.obj file
Then I use ifort compiler to compile and link to execuatble file.
ifort ftest.for ctest.obj c:\cuda\lib\cuda.lib c:\cuda\lib\cudart.lib
As expected, this will generate file ftest.exe and can output the correct result.
But when I change the name of ctest.c to ctest.cu and try to compile and link them together again,
errors occured.
nvcc -c ctest.cu
ifort ftest.for ctest.obj c:\cuda\lib\cuda.lib c:\cuda\lib\cudart.lib
Intel® Visual Fortran Compiler for applications running on IA-32, Version 10.1
Build 20080212 Package ID: w_fc_p_10.1.019
Copyright © 1985-2008 Intel Corporation. All rights reserved.
Microsoft ® Incremental Linker Version 8.00.50727.42
Copyright © Microsoft Corporation. All rights reserved.
-out:ftest.exe
-subsystem:console
ftest.obj
ctest.obj
c:\cuda\lib\cuda.lib
c:\cuda\lib\cudart.lib
ftest.obj : error LNK2019: unresolved external symbol SET_DATA in fuction MAIN
ctest.obj : error LNK2019: unresolved external symbol “int HOST_DATA_mp_A” (?HOST_DATA
_mp_A@@3HA) in function “void __cdecl SET_DATA(void)” (?SET_DATA@@YAXXZ)
ftest.exe : fatal error LNK1120: external reference unresolved。
In fact, I did nothing except changing the file extension name.
But I don’t know why the second one can not be linked normally.
Anyone can tell me the reason or how to solve this problem(acess global variables in fortran module in nvcc)?
Thank you in advance.