Date: 5 Feb 2002 22:03:03 -0400

 Typically someone who owns compiler A and is trying to write code to
 link with a third-party library that was compiled under compiler B asks
 this question.

 The answer to the question is, Not in general. Here are some of the
 reasons:

 * "Helper" functions (undocumented functions for stack checking,
   floating-point arithmetic, and operations on longs) differ between the
   two compilers.

 * Extended dictionaries are not compatible between the 2 formats.
   However, the basic structure of both MS and Borland OBJ formats is
   based on the OMF format so specifying that the linker ignore the
   extended dictionary records (/NOE for LINK, -e for TLINK) will disable
   this little hassle.

 * The compilers may embed instructions in the object code that tell the
   linker to look for their own run-time libraries. You can use the
   linker option that says to ignore such instructions: /n in TLINK, /NOD
   in the Microsoft linker (the one that comes with the C compiler, not
   the one that used to come with DOS). But getting around this problem
   will very likely just reveal other problems, like different helper
   functions, that have no easy solution.

 Those problems will generate link-time errors. Others may not show up
 until run time:

 * Borland's compact, large, and huge models don't assume DS=SS, but
   Microsoft's do. The -Fs option on the Borland compiler, or one of the
   /A options on Microsoft, should take care of this problem-once you
   know that's what's going on.

 * Check conventions for ordering and packing structure members, and for
   alignment of various types on byte, word, paragraph, or other
   boundaries. Again, you can generally adjust your code to match if you
   know what conventions were used in compiling the "foreign" libraries.

 * Check the obvious and make sure that your code was compiled under the
   same memory model as the code you're trying to link with. (That's
   necessary, but no guarantee. Microsoft and Borland don't use exactly
   the same conventions for segments and groups, particularly in the
   larger memory models.)

 That said, there are some circumstances where you can link hybrids. Your
 best chance of success comes if you compile in large model with the
 compiler switch that says to reload DS on entry to each function, avoid
 longs and floating point, use only 16-bit pointers, suppress stack
 checking, and specify all libraries used in the link.