[CMake] faking convenience libraries

[Brandon J. Van Every]

Bill Hoffman wrote:
> Brandon J. Van Every wrote:
>> Bill Hoffman wrote:
>>>
>>> You can not use FIND_* stuff because the files will not be there.   
>>> There is a risk that cmake could change where the .o files are put.  
>>> To mitigate that risk, I would recommend setting up everything with 
>>> variables.   You already have these 
>>> ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}.  That will give you the 
>>> CMakeFiles directory, then each library is in LibName.dir and the 
>>> obj files should be in there.   It would be safest to write a macro 
>>> that converts a source name into a .o name, that way if cmake 
>>> changes, you can just change the macro.
>>
>> How will I extract the type of build at configuration time?  
>> Currently I'm using code such as:
>> SET(PCRE_FOR_SHARED_OBJ_DIR
>> ${CMAKE_CURRENT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/libpcre-for-shared.dir/${CMAKE_BUILD_TYPE}) 
>>
>>
>> but CMAKE_BUILD_TYPE has no value when running CMakeSetup for VS71.
> Use CMAKE_CFG_INTDIR.  For VS IDE projects the object files will be in:
>
> ${CMAKE_CURRENT_BINARY_DIR}/libpcre-for-shared.dir/${CMAKE_CFG_INTDIR}

It seems that MSVC and MSYS don't use CMAKE_FILES_DIRECTORY in the same 
way.  I can do IF(MSVC), but are there going to be any more 
per-generator variations in directory structure?  Also I'll have to 
document the behavior of CMAKE_FILES_DIRECTORY better on the wiki.  
Previously I said that's where CMake generated files live, and for MSVC 
this is not the case.


Cheers,
Brandon Van Every