Re: Compile warning when using exported symbols located in other loadable module

[Tony Asleson <stackframe@xxxxxxxxxxx>]

Martin Jambor wrote:

> It seems you don't have the function prototype in any header file
> included in that source file.
Actually I do have a prototype in a shared header file.  If I don't 
include the prototype (the declaration) I get the following warning

make -C /lib/modules/2.6.10-1.770_FC3/build 
M=/home/tony/learnexport/user modules
make[1]: Entering directory `/lib/modules/2.6.10-1.770_FC3/build'
 CC [M]  /home/tony/learnexport/user/user.o
/home/tony/learnexport/user/user.c: In function `user_init':
/home/tony/learnexport/user/user.c:11: warning: implicit declaration of 
function `some_exported_symbol'
 LD [M]  /home/tony/learnexport/user/usesexport.o
 Building modules, stage 2.
 MODPOST
*** Warning: "some_exported_symbol" 
[/home/tony/learnexport/user/usesexport.ko] undefined!
 CC      /home/tony/learnexport/user/usesexport.mod.o
 LD [M]  /home/tony/learnexport/user/usesexport.ko
make[1]: Leaving directory `/lib/modules/2.6.10-1.770_FC3/build'

in addition to the original warning I am trying to resolve.  I believe 
the warning I'm trying to resolve is basically what would normally be a 
linker error as it cannot find the definition of the function.  In my 
case the code resides in another module.  The mainline kernel tree must 
have a way to handle this as I don't get these types of warnings when 
compiling the standard kernel modules.

Thanks,
-Tony

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