[CMake] FindBoost.cmake issue while targeting 32-bit build on Linux 64-bit

[Mateusz Loskot]

Hi,

Here is the situation outlined:
- project has Boost as optional dependency
- running CMake on Linux 64-bit to build 32-bit binaries
- CXXFLAGS=-m32 is specified
- Boost 64-bit binaries are installed
- Boost 32-bit binaries are *not* installed

Expected result:
- Boost 32 is not found, Boost is *not* enabled
- 32-bit build is configured without Boost at all
- success

Actual result:
- Boost 64 is found, Boost is enabled
- 32-bit build is configured to link against Boost 64-bit libraries
- failure

Am I missing anything in the build configuration
or FindBoost.cmake is unable to do what I expect it to do,
by design or by a bug?

Best regards,
-- 
Mateusz  Loskot, http://mateusz.loskot.net