2012/4/12 Robert Dewar <de...@adacore.com>: > On 4/12/2012 4:55 AM, Fabien Chêne wrote: > >> I've got a radically different experience here, real bugs were >> introduced while trying to remove this warning, and as far as I can >> tell, I've never found any bugs involving precedence of&& and || -- >> >> in the code I'm working on --, whose precedence is really well known >> from everyone. > > > You simply can't make a claim on behalf of everyone like this, and it's > very easy to prove you wrong, i personally know many competent programmers > who do NOT know this rule.
I should have said: from everyone with whom I work. I'm not claiming that this warning is useless for everybody, I'm basically saying that it is often a nuisance/risk to convert existing code to bypass this warning. > In the real life, things are not as simple as (a&& b) >> >> || ( c&& d), some checks usually lie over more than five lines. This >> >> warning applied to such checks are really a pain to remove. > > a) complex conditionals over five lines are a bit of a menace > anyway, I agree, they are actually a menace, and I do not want to touch them without a good reason. Adding parentheses does not improve readability, nor does it solves bugs in my own experience. Anyway, precedence rules have to be known in order to remove the warning. > but ones that rely on knowing this precedence rule are > a true menace if you ask me. G++ has not warned about this for decades, so whether or not people assuming basic precedence rules to be known are a menace, code that does not make precedence explicit, is quite common and we have to cope with it. And hopefully I'd rather not fix it everywhere. > b) it should be trivial to remove this warning, as it is a simple > automatic refactoring that should be easily done with a tool (most > certainly the automatic refactoring available in GPS for GNAT would > take care of this, if it needed to, which it does not, since in Ada > parentheses are required in such cases (the designers of Ada most > certainly disagreed with you that everyone knows this warning). If you are aware of a simple tool that do that for C++, I am all ears ... But I'd rather have a new option to disable it ;-) -- Fabien
