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c++dynamicstatic-librarieslinker-errorsbulletphysics

C++ Linking static librarys to a dynamic library

It's a bit annoying.

I have a project that is entirely dynamically linked, but I want to use a library that seems to be only designed to be statically linked, using the /MT flags, Is it possible to build a separate dll to link to the static libs and then link to that In my project?

I apologise for the rushed explanation, I'm quite tired.

The library in question is the bullet physics library.

Edit: Well, with more googling, it appears that there can be a /MD/MDd compiled version, though I'm not sure where It's located.

Edit(for anyone interested): According to this page: http://www.bulletphysics.org/Bullet/phpBB3/viewtopic.php?f=9&t=3846

"If your entire engine is compiled with the /MD flag then you would use the 'release DLL' version of bullet. You should not mix libraries compiled with /MD with ones compiled with /MT. That's the main difference. There is no "separate DLL (.dll)" files for bullet."

Edit: And If I build it using the MSVC Runtime library, then it fails.

In short, I have no idea what to do.

He's what I'm doing:

Building the whole library in cmake, using the Visual studio 12, 2013 compiler. Then building the project built by cmake, to build all the required projects.

This is the supplied instructions. Here

Last Edit:Thank you all so much for you help! I managed to build it in the end

Sorry for any spelling mistakes, I was quite tired at the time :3

Solution

  • Short answer, yes.

    Although you could just have the dynamic libraries link to it, there are scenarios where this may cause serious problems, depending on how the library was written (state information, etc.).

    Although it's more work, a wrapper DLL is probably the safest course of action. However, this is offset by the fact that you only need to wrap the functions actually called from the various components of your application, not the entire API provided by the library. Also, you'll need to have some kind of slight rename to the functions you actually wrap, to prevent ambiguity.

    On edit: Just took a look at the bullet physics library, as I was not personally familiar with it and was curious about your options after I initially answered. If they're that explicit about not supporting dynamic builds for the library, I think wrapping whatever functions you actually use would definitely be safest. That sucks. I hope it's not too large of a cross-section.