Andrea Arcangeli writes:
> cases if the code breaks in the actual usages of xtime it is likely that
> gcc is doing something stupid in terms of performance. but GCC if it
> wants to is allowed to compile this code:
>
> printf("%lx\n", xtime.tv_sec);
>
> as:
>
> unsigned long sec = xtime.tv_sec;
> if (sec != xtime.tv_sec)
> BUG();
> printf("%lx\n", sec);
And if it does that, it's stupid. Why on earth would GCC add extra
code to check if a value hasn't changed? I want it to produce
efficient code. What's next? Wrap checking?
printk ("You've just wrapped an integer: press [ENTER] to confirm,
[NT] to ignore ");
Regards,
Richard....
Permanent: rgooch@atnf.csiro.au
Current: rgooch@ras.ucalgary.ca
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This archive was generated by hypermail 2b29 : Mon Jul 23 2001 - 21:00:17 EST