I recently received a new 64-bit laptop and is my first endeavor into 64-bit computing. I installed all my usual packages through yum (I am using fedora 64 bit) and it downloaded all the 64-bit versions of the packages. I went to install an rpm packaged by years ago by a colleague at my university and the installer notified me that I had to install the 32-bit versions of about 40 dependencies (the dependencies of the dependencies as well). Now I have a lot of questions and can't find the answers. I would appreciate some feedback on my two largest questions:
1a - If I have both versions of a library, say libABC.x86_64 and libABC.i686 (the 64 and 32 bit versions of libABC) how does the compiler (I always use cmake) know to use the 64 or 32 bit version?
1b - If I install the 32 and 64 bit versions of all the packages and compilers, do I now have to specify which compilers I use?
2 - I had installed OpenCV yesterday (downloading all the 64-bit dependicies prior) via the git source code. Now I was curious to see if OpenCV had installed its libraries into /usr/local/lib or /usr/local/lib64. It installed in /usr/local/lib. What's the deal? This code was compiled using 64-bit dependecny libraries using 64-bit compilers (all located in /usr/lib64) and it installed it's libraries into a 32-bit directory. Am I supposed to specify otherwise?
Thatnks for your time, looking forward to any feedback you can give.