Floating point performance issue
Miles Bader
miles@gnu.org
Thu Dec 22 03:23:00 GMT 2011
2011/12/21 David Brown <david@westcontrol.com>:
> I think our key difference of opinion here is that you want a warning only
> when it is quite clear that "something dodgy" is happening - I want the
> warning unless it is quite clear that something dodgy is /not/ happening.
Er, well feel free to turn on the warning for code you write...
But the _default_ settings (and what's included in "catch-all" options
like -Wall) are something altogether different. They are a balancing
act, and must take into account many different programming styles, and
avoid excessive false positives[1], which are quite annoying,
especially when there isn't a clear alternative to what's being warned
about[2]. False negatives are less of an issue, as typically
"something is better than nothing"...
[1] Yes, in this case, a warning about a valid comparison _is_ a false
positive; the warning says "this is unsafe" for a comparison that is
safe
[2] E.g., "if (x = ...)" can be trivially rewritten as "x = ..; if
(x)", and doing so generally improves code readability without any
runtime penalty; however this isn't true for all constructs
-miles
--
Cat is power. Cat is peace.
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