Sean Kelly wrote:
On Aug 18, 2011, at 10:29 AM, Nick Sabalausky wrote:
"Bernard Helyer" <[email protected]> wrote in message
news:[email protected]...
I asked the Ars forums ( http://arstechnica.com/civis/viewtopic.php?
f=20&t=1153378&p=21965411 ) and I ask the same of you: should
unambiguously unreachable code be an error or a warning? ( see the linked
forum post for more details ).
No. That would be a royal pain in the ass during debugging. I expect to be
able to stick a "return xxxx;" anywhere I want to test something and not
have the compiler crap out because I didn't deal with the overhead of
commenting out the rest.
A warning might be nice, though.
A warning if anything. I've never encountered a situation where code was made
unreachable by accident. I also get "unreachable code" warnings periodically,
for code that is absolutely reachable. I don't want my code to not compile simply
because the compiler can't perform adequate flow analysis.
I have encountered bugs of the form:
if (cond) { /* unreachable */ }
and the cond was unintentionally always false. The last time I
encountered such a bug was last week. I'm surprised your experience is
so different.
It's crucial that it should never report "unreachable" if it is unsure
(not even a warning).
But I think conditional compilation is a huge problem -- code may be
valid under different compilation conditions. I suspect that to
eliminate all the false positives, it'd have to be so conservative, that
it wouldn't catch any bugs.
