Re: Unusual (to me) local variable corruption problem

I have a fairly prosaic Win32 GUI app that corrupts an int local to
one of my functions. Changing the position of the int on the
function's stack "solves" the problem, as if I'm writing something to
the wrong location, but a dummy variable placed in that location does
not suffer the same fate. Nor does placing large dummy arrays on
either side of the problem variable (which of course dramatically
changes its location relative to its active neighbors) isolate the
problem variable from its unknown assailant.

Changing the name of the problem variable (throughout the function
it's in, of course) solves the problem.

That variable name (nFileReq) is not used at a higher scope in the
program, although it's reused as a local in other functions, as well
as in argument lists for other functions.

Changing the variable name globally *except* in the problem function
does not correct the problem.

The dev environment is VS6SP5 iirc. The problem is only seen in the
release build, which probably doesn't say anything except that stuff
is different between the two, but it makes it more difficult to debug.

The program uses OLE to open a couple of instances of Excel and
manipulate the spreadsheets. Besides the main thread there's one
other, and the problem is in that thread function (which is created
with CreateThread, fwiw.). It happens across a call to an OLE function
that populates an Excel cell. That function takes a pointer to an int
(on the calling function's stack, of course, thus "near" the problem)
but otherwise doesn't obviously relate to the problem. Except of
course that it does, just not obviously.

Thoughts?