32 bit library on 64 bit system

Can it cause any pr开发者_开发问答oblem if I use 32 bit library on a 64 bit system?

What could be the incompatibilities?

I know this question is too vague. An example :

I tried to setup FreeGlut 32bit library with VS2010 on windows 7 64bit. There were a lot of issues at first.So, I was looking for 64bit of FreeGLUT, thinking 32bit FreeGlut might conflict with 64 bit windows. But later on I managed to run my 32bit FreeGlut with my 64bit windows without any problem.

Question is, if there are any thing in the program, that we should look into while using those libraries which doesn't match with the system. (32bit library on 64 bit OS)

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64 bit Windows is fully capable of running 32 bit applications. In fact, the default configuration for Visual C++ is to build an x86 application regardless of the operating system it is running on.

There are some gotchas you have to be aware of when running a 32bit app on 64bit Windows. For instance, there's registry redirection (to avoid it you pass KEY_WOW64_64KEY to e.g. RegOpenKeyEx). There's filesystem redirection, too. These are important things to have in mind when you are reading system configuration values, for example.

Also, be aware that you can't mix 32 and 64 bitness in the same process. Your 32bit app can't use 64bit DLLs or static libraries.

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Visual studio can compile for 32 bit or 64 bit based on the project setting.

Probably, Question you mean to ask is about Linking 32-bit library to 64-bit program

The answer is:
You can't directly link to 32bit code inside of a 64bit program.
The only option is to compile a 32bit (standalone) program that can run on your 64bit platform (using ia32), and then use inter-process communication to communicate to it from your 64bit program.

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It's not about the operating system- Windows doesn't care if your code is 32bit or 64bit. It matters that your process is the same bitness as all libraries it cares to load- and they must all be the same bitness.

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You might be interested in this link explaining common compiler errors when porting to 64-bit. It might help you solve your problem.

To try to answer your question more directly, there are things that might make 32 bit libraries break in a 64 bit environment, but that's too much information to share in a SO answer.

This link is the MSDN index related to development for 64 bit systems and might interest you as well.

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Your question could be about how to develop specifically code that will run natively on 64-bit versus 32-bit hardware. There is info on that here. In particular you would have to follow the instructions here to enable 64-bit build tools.

If you are building 64-bit binaries, you will need to link with 64-bit libraries. Note that 32-bit binaries should run just fine on 64-bit Windows, so you may not need to go to this trouble.