[CMake] FindBoost.cmake oddities

[Mike Jackson]

Andreas Pakulat wrote:
> On 11.12.08 11:38:38, Mike Jackson wrote:
>> Up a bit further I see the culprit:
>>
>>   IF ( WIN32 AND Boost_USE_STATIC_LIBS )
>>     SET (Boost_LIB_PREFIX "lib")
>>   ENDIF ( WIN32 AND Boost_USE_STATIC_LIBS )
>>
>> So I guess I need some logic in my own cmake files that says if Boost  
>> was NOT found, set Boost_USE_STATIC_LIBS to TRUE and try again, only if  
>> we are on Win32. I am sure I am missing something simple...
> 
> The problem is with mixed boost installations, i.e. you have shared and
> static libs. If you have that there's no way to force cmake into finding
> the static version other than changing the suffix variable as cmake will
> always prefer shared over static libraries.
> 
> I'm not sure about the lib prefix above, it might be that this is only
> really needed for mingw and not for VS.
> 
> Andreas
> 

I think it is only needed for msvc. MinGW uses the more unix way (I 
think) of naming libraries. libFoo.so?

MSVC does Foo.dll + Foo.lib for dynamic libraries and libFoo.a for 
static libraries.

The logic for Mixed installations should be able to be designed.

say we have set (Boost_PREFER_STATIC_LIBS)

now, down in FindBoost.cmake we would need the following table in CMake 
code created:

           static  dyn  use_static
static      1      0       0
static      1      0       1
dyn         0      1       0
warning     0      1       1
dyn         1      1       0
static      1      1       1
error       0      0       0
error       0      0       1

Col 1: Which libs get set into the Boost_LIBRARIES variable
Col 2: Were Static Libraries Found
Col 3: Were Dynamic Libraries Found
Col 4: Was use_static set to true

There is going to be some more logic to this to special case the 
program_exec_monitor which is ALWAYS static and NEVER dynamic.

Just my thoughts....

Mike.