[Info-vax] decrementing & for loops in C

[nobody]

vaxinf at chemie.uni-konstanz.de wrote:
> Hi,
> 
> I tried to run one of the example found on Jim Duff's homepage and
> found a behavior of for loops written in C:


Others have commented about the program not working, so I won't.

Another thing you may experience with some compilers is that the result 
will be that both loops go in the same direction no matter what you 
write. The reason beeing that an optimizing compiler may realize that 
you are not doing anyting inside the loop that forces you to do it in a 
special order. Therefore it may choose to turn one of them around in 
order to do the execution faster.

I must admit I have never seen this in a C program since I'm really not 
a C programmer. But I have seen it in Ada and in Pascal.

Turning off optimization should normally cause the program to execute 
your program exactly as written.

/L