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Some small issues with TheIDE and DLLs [message #22290]

Wed, 01 July 2009 04:58

cbpporter
Messages: 1401
Registered: September 2007

Ultimate Contributor

I need to generate a DLL from TheIDE which exports some functions with implementations that use U++ classes.

First I tried setting the "All shared" option. This was a long shot and I was sure it wouldn't work, but the build process crashed. It shouldn't crash.

After some searching on the site I found that you are supposed to set the "DLL" configuration flag. This seems to have worked. I get a rather large DLL (probably the linker doesn't know what to exclude and includes all), an ".exp" file and a ".lib" file. Everything seems to work. Except when I hit run, I get a nice error message that the DLL can't be run (which is true of course) and a nice crash. It shouldn't crash.

But when building with MINGW I don't get the ".lib". This is needed if I don't do manual loading of the DLL. (Also the DLL is more than twice as big when compared to the MSC version, but I guess this is to be expected).

I have a few questions:
1. Should I compile with USEMALLOC option. Will U++'s malloc implementation cause problems if I free in the client application something allocated by the host? Will it be okay if all allocation and freeing is done by calls to the DLL?
2. Will there be issues with "icpp"s and other initialization tricks that U++ uses?
3. Can I use the the "DLL" flag under Linux or must it be changed to "SO". Same issue, I don't want a .so for every package, I want one big one.
4. Is there some macro provided by U++ as a platform independent equivalent of __declspec(dllexport) for writing DLLs?
5. What happens to global variables. What if my functions alter such variables. Will there be multiple such instances for different clients or will they override each other. Can this cause problems with all the global variables U++ uses internally? And is this behavior consistent across platforms?

Thank You

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