On Fri, Feb 5, 2021 at 5:23 PM David Laight David.Laight@aculab.com wrote:
From: Andy Shevchenko
Sent: 05 February 2021 12:51 On Fri, Feb 5, 2021 at 1:35 PM Richard Fitzgerald rf@opensource.cirrus.com wrote:
On 04/02/2021 16:35, Petr Mladek wrote:
On Wed 2021-02-03 21:45:55, Andy Shevchenko wrote:
On Wed, Feb 03, 2021 at 04:50:07PM +0000, Richard Fitzgerald wrote:
...
- for (; max_chars > 0; max_chars--) {
Less fragile is to write
while (max_chars--)Except that the original was more obvious at least for me. I always prefer more readable code when the compiler might do the optimization easily. But this is my personal taste. I am fine with both variants.
I *slightly* prefer while-loop *in this case* due to less characters to parse to understand the logic.
The two loops are also have different values for 'max_chars' inside the loop body.
off-by-one to be precise.
If 'max_chars' is known to be non-zero the do ... while (--max_chars); loop will probable generate better code.
What?! while (--x) and while(x--) are equivalent.
But there is no accounting for just how odd some decisions gcc makes are.
Why should we care about the compiler bugs here?