Do I Need Multilib?

If you have a CPU that is capable of multilib, it is time to decide whether to go for it or not. Depending on the circumstance, it may be necessary to go for it.

Steam

Most gamers would not know this unless they push the limits of the game they play, but many games on Steam are 32-bit. Some games are no longer receiving updates while some are still being updated but are still 32-bit to this day.

Not only are a lot of games 32-bit, but Steam itself requires that you have 32-bit libraries. If the 32-bit libraries aren't on the system, Steam will quit, saying it needs a library, libc.so.6 being the most common example. So if you have a 64-bit CPU, you will need the ability to execute 32-bit applications as well as all the libraries necessary which is laid out in Chapter 3.

If you have a 32-bit CPU, you can skip the 32-bit libraries and compile everything normally as they will build for your architecture.

[Important]

Important

Steam will eventually kill off 32-bit CPU support so be wary that while you can run Steam with a 32-bit CPU, in the future perhaps sometime soon, you will no longer be able to do this.

Wine

Unlike Steam, Wine does not require that you have 32-bit libraries or the i686-w64-mingw32 toolchain. Moreover, to get multilib support in Wine, it must be compiled twice: a w64 build and a w32 w/ w64 build. However, it was discussed eariler in the Steam section that many games are 32-bit and are no longer maintained or will take a while to switch to 64-bit. This is the case with Windows applications as well. This means that if you do a 64-bit only build, compatabilty for all those 32-bit applications will be lost.

A Wine WoW64 (can run 32-bit and 64-bit applications) build is recommended. If you do not have a 64-bit CPU, then follow only the i686 build instructions. Likewise, if you have a 64-bit CPU, then you can follow only the x86_64 build instructions. The mingw-w64 toolchain is also really helpful for developers, so if you don't want full support with Wine but full support for the mingw-w64 toolchain, then by all means: go for it.