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  • src/xpdev/wrapdll.h

    From rswindell@VERT to CVS commit on Fri Mar 22 14:29:46 2019
    src/xpdev wrapdll.h 1.7 1.8
    Update of /cvsroot/sbbs/src/xpdev
    In directory cvs:/tmp/cvs-serv32122/xpdev

    Modified Files:
    wrapdll.h
    Log Message:
    Use default calling convention (__cdecl) for DLL funcs in Borland builds.

    Fix age-old bug with Borland/C++Builder built executables (Windows):
    to achieve compatibility with the default __cdecl symbol naming rules of Visual C++, we were using __stdcall convention for DLL functions when
    building code with Borland/C++Builder tools and using the default (__cdecl) convention when building with Microsoft (Visual C++) tools. Although this allowed symbols to be located when linking, the calling convention mismatch caused a stack cleanup issue that very rarely manifested itself in a bug
    (e.g. exception of some kind in sbbsctrl.exe, usually). Mismatching
    the calling conventions was unintentional (I thought the default for MSVC
    DLL functions was __stdcall) - but since the calls to MSVC-Built DLL functions worked 99% of the time, I didn't realize there was an underlying issue. So I now work-around the DLL symbol naming mismatch using a command-line option (-a) passed to implib in src/sbbs3/ctrl/makelibs.bat

    I had previously worked-around exceptions when calling MSVC DLL functions in sbbsctrl.exe by calling the problematic DLL functions from a timer tick handler rather than a user control (e.g. button) event handler. Those work-arounds can now be removed.

    The erroneous "DLLCALL" definition design pattern was replicated (copy/pasted) to many other projects' header files in cvs.synchro.net. In the future, we may want to just remove all instances of *CALL since they now serve no purpose and appear as useless "Kruft" (but do allow us to more-easily globally change DLL function calling conventions if/when necessary in the future).


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