Bug 43841 – SegmentedVector::operator== typo

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[andreyf]

WTF::SegmentedVector::operator== (in file webkit\JavaScriptCore\wtf\SegmentedVector.h:70) has typo:
        bool operator==(const Iterator& other) const
        {
            return (m_index == other.m_index && m_segment = other.m_segment && &m_vector == &other.m_vector); // HERE: m_segment _=_ other.m_segment
        }

This should be:
        bool operator==(const Iterator& other) const
        {
            return (m_index == other.m_index && m_segment == other.m_segment && &m_vector == &other.m_vector);
        }

Because normaly operator== should be ! operator!=.

        bool operator!=(const Iterator& other) const
        {
            return (m_index != other.m_index || m_segment != other.m_segment || &m_vector != &other.m_vector); // NOTE: m_segment _!=_ other.m_segment 
        }

I don't know consequences of this.

Kind regards,
Andrey

[Darin Adler]

Looks bad! I wonder what the symptom is.

[Geoffrey Garen]

It looks like the operator isn't used. I'd suggest removing it.

[andreyf]

(In reply to comment #1)
> Looks bad! I wonder what the symptom is.

Darin, unfortunately, this was found by my code intrumentation utility and i don't have time to compose a unit test to reproduce erroneous behaviour.
I promise to try later.
Why don't change this to something like:
        bool operator==(const Iterator& other) const
        {
            return ! operator!= (other);
        }
It will not consume much code space and provide full external interface to SegmentedVector. 

Kind regards,
Andrey

[Geoffrey Garen]

I'm not keen on having unused / untested code in the tree. It leads to bitrot like this.

If you plan on using this function, that's a different story.

[Darin Adler]

Yes, lets remove the function as Geoff suggests.

[Gavin Barraclough]

Fixed in r88892.  (These operators are used by the DFG JIT).

[Gavin Barraclough]

*** Bug 56289 has been marked as a duplicate of this bug. ***