Re: RFC: #pragma optimization_level

[E. Weddington]

Georg Bauhaus wrote:
We have just been discussing a similar topic in a de.* newsgroup.
A busy-loop function is used to effect a delay, not too precise,
but portably. Like
#define COUNT 1000
void f() {
  /*volatile*/ /*register*/ int i;
  for (i = 0; i < COUNT; ++i)
         ;
}
If volatile is used to instruct the compiler to actually produce
a loop even when optimizing, then we get copying from/to the stack,
or memory access (ARM). What the compiler users have expected their
compiler to do is to produce an obvious loop using registers.
What do you get if you use the C99 construct of declaring the variable 
in the for statement? Like so:

for(volatile int i = 0; i < COUNT; ++i);
Eric