https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94767
jh718.park at samsung dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |RESOLVED
Resolution|--- |INVALID
--- Comment #4 from jh718.park at samsung dot com ---
(In reply to Jonathan Wakely from comment #3)
> (In reply to jh718.park from comment #0)
> > For these variables below,
> >
> > unsigned m_schemeEnd : 26;
> > unsigned m_userStart;
> >
> > m_userStart == m_schemeEnd + 1
> >
> > this comparison emits a compiler warning as below.
> >
> > warning: comparison of integer expressions of different signedness:
> > ‘unsigned int’ and ‘int’ [-Wsign-compare]
>
> Why do you think that's wrong?
>
> In [conv.prom] p5 the standard says:
>
> "A prvalue for an integral bit-field (11.4.9) can be converted to a prvalue
> of type int if int can represent all the values of the bit-field;"
>
> Since int is wider than 26 bits it can represent all the values of
> m_schemeEnd, so the operands of 'm_schemeEnd + 1' are both promoted to int,
> and the result is an int.
Thank you for your comment, Jonathan.
I understand your point.
I thought that unsigned bitfield should be converted to unsigned
during usual arithmetic conversions without knowing the item,
http://eel.is/c++draft/conv.prom#5.
Then, I will mark this issue as resolved/invalid, and update the bug
https://bugs.webkit.org/show_bug.cgi?id=211044
with the comment you left here.
Thank you for your help:)
