[CMake] How to relink executables when depdent library got changed ?

[Michael Wild]

On 11.06.2009, at 15:44, Bill Hoffman <bill.hoffman at kitware.com> wrote:

> Chih-pin Wu wrote:
>> Hi all:
>>  I'm working on an embedded platform and building integrated  
>> software as multimedia CE devices. And I am just started trying to  
>> introduce CMake to replace my legacy environment constructed by  
>> many hand-written gnu styled makefiles.
>>  I have many components which is cross referred to each other very  
>> complicatedly, and it really helps a lot when I started to migrate  
>> to CMake with the benefit of automatic dependency checking.
>>  However, my order of building is
>> i) build lots of libraries, called components
>> ii) then build final executable, called application, linking with  
>> libraries
>>  I really felt comfort when I modified some header files in the  
>> component directory, and makefiles generated by CMake automatically  
>> found it, rebuild all dependent source files as well as the  
>> libraries.
>> However I could not make my final executable link those libraries  
>> automatically when libraries got changed.
>>  I used TARGET_LINK_LIBRARIES to enumerate linking libraries, also  
>> ADD_DEPENDENCIES with these libraries.
>> But I still can't make it relink to a executable when those  
>> libraries got changed, no matter it's rebuilt by makefile or  
>> replaced by some newer revision.
>
> Can you post some of your cmake code?  This should work.  I suspect  
> that you are not using full paths to libraries in  
> target_link_libraries. add_dependencies should not be needed.
>
> -Bill
>

Actually, of your libraries are CMake targets themselves, everything  
should work out of the box. I.e.:


add_library( comp1 file1.c file2.c )
add_executable( gadget file3.c file4.c )
target_link_libraries( gadget comp1 )

should create the library comp1 and the executable gadget, linking it  
with the comp1 library. All with automatic dependency tracking.

HTH

Michael