[cfe-dev] Missing warning when binding to const ref?

[Daniel Dilts]

Ah!  I finally see where your issue is.  This problem is probably better
suited for static code analysis.  For a trivial example like this you can
pretty quickly track down what is wrong, but for the more general case I
don't imagine that this being a check that can be done quickly enough for a
compiler warning.

On Tue, Apr 7, 2015 at 8:04 PM, Nikola Smiljanic <popizdeh at gmail.com> wrote:

> I should have made a better comment, the types are different! Parameter
> needs to be implicitly converted to int, and we're binding a a const ref to
> this temp object whose lifetime ends once S is constructed. Unless I'm
> mistaken.
>
> On Wed, Apr 8, 2015 at 1:01 PM, Daniel Dilts <diltsman at gmail.com> wrote:
>
>>
>>
>> On Tue, Apr 7, 2015 at 6:11 PM, Nikola Smiljanic <popizdeh at gmail.com>
>> wrote:
>>
>>> I'm surprised this doesn't produce a warning:
>>>
>>> struct S
>>> {
>>> S(const int& i) : i(i) {}
>>> const int& i;
>>> };
>>>
>>> void foo(long l)
>>> {
>>> S s(l); // binding a const ref to temporary
>>> }
>>>
>>> int main()
>>> {
>>> foo(1l);
>>> }
>>>
>>>
>>> Why would that produce a warning?  You can bind an r-value to a const
>> l-value reference.  And, function foo takes the parameter by value, so it
>> is passing an l-value to the constructor of S.
>>
>>
>
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