TIP: Click on subject to list as thread! ANSI
echo: os2prog
to: Jeff Dunlop
from: Jonathan de Boyne Pollard
date: 1995-08-25 11:18:12
subject: system lockups

JD>
  > JdeBP> Incidentally, the C++ startup for many DOS compilers is still writ
  > JdeBP> for the 8086 and its bugs, and contains the following sequence :
  >
  > JdeBP>   cli
  > JdeBP>   mov ss,_seg
  > JdeBP>   mov sp,_off
  > JdeBP>   sti
  >
  > JdeBP> So a *lot* of DOS applications Out There will be doing CLIs for no
  > JdeBP> good reason, in their startup code.
  >
  > Isn't this reasonable for a Dos program that runs in a VDM
  > alongside a TSR?
JD>

  No.  AFAIAA the 80286 and later provide means of loading the stack
  segment and offset together as one atomic operation.  As I said, the
  problem is that many DOS compilers still contain code written for the
  8086 and 80186 and their bugs.

  > JdeBP <
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