3 Dec
2010
3 Dec
'10
2:47 p.m.
On Dec 3, 2010, at 2:42 PM, Fred Cisin wrote:
See my previous post. Using the volatile keyword on a variable requires the compiler to
read/write it as expressed in the program (ie if in a loop, the compiler can't just
read it once and be done). If the compiler doesn't do that, it's a bug if it in
any way claimed be a standards compliant compiler.
TTFN - Guy
> I'm
afraid I must disagree. What if, for my own nefarious purposes, I
> need the N microseconds of delay achieved via the "spurious" for loop?
On Fri, 3 Dec 2010, Richard wrote:
Put that code in a compilation unit that is
compiled with
optimizations turned off.
Whether a programmer or a compiler produce better code would seem to
depend on how well one can get the compiler to understand all of the
details of what one WANTS the code to do, and just how weird THAT might
be. Some things, such as deliberately wasting time, or polling a memory
location that is influenced externally, need additional explanation for
the compiler to understand not to optimize them out.