Bug 125122 – DFG logic mixes boolean and binary operations

• Status: RESOLVED
• Resolution: DUPLICATE
• Component: JavaScriptCore

[Brent Fulgham]

DFGCommon generates a bunch of warnings when built under Windows:

7>c:\projects\webkit\opensource\source\javascriptcore\dfg\DFGCommon.h(216): warning C4805: '==' : unsafe mix of type 'bool' and type 'int' in operation
7>          c:\projects\webkit\opensource\source\javascriptcore\dfg\DFGVariableAccessData.h(96) : see reference to function template instantiation 'bool JSC::DFG::checkAndSet<bool,int>(T &,U)' being compiled

The offending code in DFGVariableAccessData looks like this:

    bool mergeIsCaptured(bool isCaptured)
    {
        return checkAndSet(m_shouldNeverUnbox, m_shouldNeverUnbox | isCaptured)
            | checkAndSet(m_isCaptured, m_isCaptured | isCaptured);
    }


MSVC seems to be promoting the two boolean types in the binary OR operation (e.g., m_shouldNeverUnbox | isCaptured) to integer type, which is then passed to checkAndSet, resulting in a comparison of bool to integer.

Probably harmless, but an annoying warning.

[Brent Fulgham]

I think Mark fixed this already. Can you confirm?

[Mark Lam]

Yes, this is fixed already in ToT.

[Mark Lam]

(In reply to comment #2)
> Yes, this is fixed already in ToT.

Specifically, this was fixed for https://bugs.webkit.org/show_bug.cgi?id=135205 in http://trac.webkit.org/changeset/174371.

*** This bug has been marked as a duplicate of bug 135205 ***