MB> I've worked extensively with Watcom 16-bit code, but I can't say
MB> that I ever  tried using the compiler default on this.  My standard 
MB> makefile always sets the packing explicitly, so I have not  run into
MB> any problems. 

I went that way, too, after making this 'newbie' mistake porting a
database program that had to access old files that used the C6
structure allignment in the data records.  Talk about garble!  C6 was
default WORD aligned, Watcom is default BYTE aligned...

MB> Where Watcom will burn you badly 
MB> when moving from Microsoft C 6.0 is in segment alignment, 
MB> since Watcom's 16-bit OS/2 compiler expects "para" aligned 
MB> segments and MS C6 requires only "dword" aligned segments.  
MB> If you try to link a MS C6 library, such as IBM's 
MB> DHCALLS.LIB for device drivers, with code generated by 
MB> Watcom, then the odds are that the linker will mess up 
MB> (although it can work by coincidence).

Here, I lucked out.  I was using all large model code with multiple
overlays, so the 16 byte alignment was already forced for all my code. 
Of course, I never compiled the OS/2 port under C6 - I switched to
Watcom way back before then for DOS/WIN apps,  and that's all I had
when the OS/2 port was made.  Hey, I gotta win one sometimes!

---
 X KWQ/2 1.2i X Of all the things I've lost, I miss my mind the most.

--- Maximus/2 2.02