[CMake] Dependency rule not included

[Vivien Delmon]

On 12/08/2010 04:50 PM, Michael Wild wrote:
> On 12/08/2010 04:28 PM, Vivien Delmon wrote:
>> On 12/08/2010 04:13 PM, Michael Wild wrote:
>>> On 12/08/2010 03:54 PM, Micha Renner wrote:
>>>> Am Mittwoch, den 08.12.2010, 14:55 +0100 schrieb Vivien Delmon:
>>>>> CMAKE_MINIMUM_REQUIRED(VERSION 2.8)
>>>>> ADD_CUSTOM_COMMAND(OUTPUT toto.h toto.c
>>>>>       COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/create_totoc_totoh.sh
>>>>> )
>>>> SET_SOURCE_FILES_PROPERTIES(toto.h toto.c PROPERTIES GENERATETED TRUE)
>>>>
>>>> See:
>>>> http://www.cmake.org/cmake/help/cmake-2-8-docs.html#command:set_source_files_properties
>>>>
>>>> and:
>>>> http://www.cmake.org/cmake/help/cmake-2-8-docs.html#prop_sf:GENERATED
>>>>
>>>>
>>>>> INCLUDE_DIRECTORIES(${CMAKE_CURRENT_BINARY_DIR})
>>>>> ADD_LIBRARY(titi toto.c)
>>>>> ADD_LIBRARY(tata tata.c)
>>>>
>>>> Greetings
>>>> Micha
>>>>
>>>
>>>
>>> the GENERATED property is set automatically by ADD_CUSTOM_COMMAND. But I
>>> suspect the problem is that you used a relative path in your OUTPUT
>>> option. *Always* specify full paths in the OUTPUT and DEPENDS options.
>>> Also, make the custom command DEPENDS on the create_totoc_totoh.sh
>>> script and it's input (perhaps it reads some configuration file or you
>>> pass it another file as an argument, etc.).
>>
>> Both solutions does not solve the problem.
>>
>> CMAKE_MINIMUM_REQUIRED(VERSION 2.8)
>> ADD_CUSTOM_COMMAND(OUTPUT ${CMAKE_CURRENT_SOURCE_DIR}/toto.h
>> ${CMAKE_CURRENT_SOURCE_DIR}/toto.c
>>      COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/create_totoc_totoh.sh
>> )
>> SET_SOURCE_FILES_PROPERTIES(toto.h toto.c PROPERTIES GENERATETED TRUE)
>> INCLUDE_DIRECTORIES(${CMAKE_CURRENT_BINARY_DIR})
>> ADD_LIBRARY(titi toto.c)
>> ADD_LIBRARY(tata tata.c)
>>
>> The problem is that tata.c include toto.h. cmake does not know it
>> because C file dependencies are constructed later by make. The result is
>> that CMakeFiles/tata.dir/build.make does not include the rule needed to
>> construct toto.h. I try to find a way to add this rule.
>> A workaround consists in putting toto.h in libtata dependencies but it's
>> not a dependency of libtata but a dependency of tata.c.
>>
>> The error is :
>> [ 33%] Building C object CMakeFiles/tata.dir/tata.c.o
>> /home/vivien/tmp/cmake_deps/tata.c:1:18: fatal error: toto.h: No such
>> file or directory
>> compilation terminated.
>>
>
> Ah, yes. I missed the "tata"<->"toto" difference ;-) In this case you
> can use
>
> set_source_files_properties(tata.c PROPERTIES
>    OBJECT_DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/toto.h)
>
> Which is, of course, less than ideal because you have to know which
> sources include toto.h. *BUT*: Actually, since tata.h is including
> toto.h, it is likely that the tata library actually needs to be linked
> against the titi library, so adding
>
> TARGET_LINK_LIBRARIES(tata titi)

Thanks it's certainly what I need. Still have to find this titi in the 
bigger project ...

> also solves the problem, but in a much cleaner way.
>
> Another thin: *never* generate output in the source tree. Actually, I
> start to think that the ADD_CUSTOM_COMMAND should error out if any of
> the OUTPUT files is located in the source tree for out-of-source
> builds... At least, it should print a big fat "developer-warning".

Yes off course, it's not the case in fact. just a fast copy/paste for 
the example.

> Michael

Thanks for your fast answer.

-- 
Vivien Delmon
PhD at CREATIS, Lyon
http://www.creatis.insa-lyon.fr/rio