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Creation of a DLL containing classes in BC 4.52

Posted on 1997-04-28
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Last Modified: 2012-08-14
I am working on a large project for Windows 3.1 16 bits. With time, I have been forced to reduce my stack more and more up to the point I couldn't do it anymore. So now I HAVE to make a DLL. It's a first for me and I am having a little trouble with it. Here's what happens:

Borland ++ version 4.52

Project->New Project

- Target type :
Dynamic Library [.dll]

-Platform :
Windows 3.xx (16)

-Target model :
Large

-Standard library :
Class library
Runtime
Static

In the IDE projet I delete the files .DEF and the .RC

In dll.cpp :

class _MYCLASS MyClass0
{
  public:
  int MyInt;
  ...
};


_MYCLASS is defined with

#if defined(BUILD_MY_DLL)
  #define _MYCLASS __export
#elif defined(USES_MY_DLL)
  #define _MYCLASS __import
#else
  #define _MYCLASS
#endif

In the project options creating the DLL, I define "BUILD_MY_DLL" and USES_MY_DLL in the project using the DLL


C++ compile doesn't have any problem

If I compile too many classes while editing the link, an extra dialog box appears while running BC45\BIN\IMPLIB.DLL.
It says "Critical error during transfer". The compilation is then stopped without error.

The problem disppears if I don't include too many classes in a module. But, if I create an other module using #include,
the problem reappears with no solution...

This method works on 3 classes. The DLL uses up 80 Kb. It's impossible
to add any more classes to end up with a DLL of over 300 Kb, for example.

If I create another project using the classes from the first, I can only define 2 classes and the second DLL only uses 60 Kb, which means it's  actually smaller than the first one.

I did not define any int FAR PASCAL LibMain(HINSTANCE,WORD,WORD,LPSTR) in the dll ...

I used impdef to declare classes in the .DEF but there was no change.

How to create a DLL without being penalised by this error?
Are there examples of IDE projects of DLL containing numerous classes?
Is there an upper limit of the number of classes in a DLL?

Sometimes I also get the following error while editing the link:
"Linker fatal : Unable to open file 'C:\BC45\LIB\c0dl.obj'"
But this file exists and is not corrupted...


So, in the end, I can have a big DLL but since implib crashes, I get a .LIB of 0 byte.

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Question by:strategem
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3 Comments
 
LVL 3

Accepted Solution

by:
gaohong earned 130 total points
ID: 1163016
Your method is correct, however, your setting seems contradictary
               
                -Standard library :
                 Class library
                 Runtime
                 Static

First you canot mix static and DLL, second you are trying to make
a DLL, and it's must be dynamic.

All the problems list, I think is followup problems, once you
made correct settings, it will be OK.

My DLL is 300K under same environment as you have win16, large,
and bc++4.52

good luck
0
 

Author Comment

by:strategem
ID: 1163017
Sorry... I forgot to mention that... I had tried both static and dynamic, with identical results.
Would you like me to send you my project via E-mail?

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LVL 3

Expert Comment

by:gaohong
ID: 1163018
Yes, Could you send *.ide file
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