Undefined reference to:

ashlesha · 11-07-2006, 09:08 PM

Hi,

I m trying to compile the linux kernel 2.6.14.6 with board support for the MIPS EncoreM3 board (AU1500 chip).

I have an irq.c function in the arch/mips/au1000/encm3/ directory and in another file, board_setup.c, in the same directory i make the following assignment:

Quote:

board_init_irq=encm3_board_init_irq;

I get this error when I try to compile

Quote:

arch/mips/au1000/encm3/lib.a(board_setup.o)(.init.text+0x4c): In function `board_setup':
: undefined reference to `encm3_board_init_irq'
arch/mips/au1000/encm3/lib.a(board_setup.o)(.init.text+0x50): In function `board_setup':
: undefined reference to `encm3_board_init_irq'
make[1]: *** [.tmp_vmlinux1] Error 1
make[1]: Leaving directory `/home/ashlesha/KNP-Linux/linux'
make: *** [build] Error 2

Can someone help me out here?

Thanks,
Ashlesha.

nadroj · 11-07-2006, 09:20 PM

where IS 'encm3_board_init_irq' declared/defined? does the compiler 'know' where it is in this program?

ashlesha · 11-07-2006, 09:23 PM

encm3_board_init_irq is defined in the irq.c file in the arch/mips/au1000/encm3/ directory and how do i knw if the compiler knows where the program is?

i think the board_setup.c file is being compiled before the irq.c file which is why the compiler cant find the encm3_board_irq_init function..

Thanks,
Ashlesha.

nadroj · 11-07-2006, 09:26 PM

is there a header you need to include? like irq.h?

orgcandman · 11-08-2006, 09:10 AM

the issue boils down to the linker being unable to resolve that particular dependancy.

When the linker starts putting your object files together, its going to look up any undefined symbols, and symbols which are duplicately defined or redefined, and attempt to resolve those issues. If it can't find a symbol, that means you're not linking the definition of that symbol into the final product.

What you might want to do is expose some API to an upper layer routine which will have both of these libraries linked into it, and have THAT make the assignment. That's, at least, one way of solving this issue quickly.

ashlesha · 11-08-2006, 02:07 PM

Hi,

Thanks for your responses -- I did not receive notification of the same so could not respond earlier.

I do include a header irq.h in the board_setup.c file.

Quote:

What you might want to do is expose some API to an upper layer routine which will have both of these libraries linked into it, and have THAT make the assignment. That's, at least, one way of solving this issue quickly.

When you say it has "both libraries linked into it", do you mean
a) a routine which has all the # include files from board_setup.c as well as irq.c?

OR

b) a routine which calls functions from both these files?

Thanks again for your response,
Ashlesha.