Re: When I'm 64 ( nsFrameStateBits.h )

Using state bits makes us very aware of how many we've used, and when 
we're about to run out (and change the compiled size of the class).

We'd want static asserts or similar to track this instead if we switched.

- Matt

On 14/02/16 4:34 PM, [email protected] wrote:
> On Saturday, February 13, 2016 at 6:56:17 PM UTC-8, Xidorn Quan wrote:
>> On Sun, Feb 14, 2016 at 10:21 AM, L. David Baron wrote:
>>> It looks like there's a 32-bit gap on 64-bit builds next to
>>> mOverflow, and we should probably just put another 32 bits of frame
>>> state bits there (after double-checking this).  We might want to
>>> separate the class-specific bits into that new 32-bit value,
>>> although I'm less sure about that.
>> If we are putting class-specific bits into separate area, are there
>> any reason we still perfer the current setting (state bits) over bool
>> bitfields?
>>
>> It seems to me using bitfields would give us more flexibility on
>> adding and removing flags, and potentially provide more compile time
>> check.
>>
>> I guess we would probably still want to keep bits of text frame in the
>> same place?
>>
>> - Xidorn
> I suppose that if a struct/class of 32 booleans fits in that 32-bit gap, then it should be OK memory-wise. I don't know if this gets compiler-specific re: alignment.
>
> --Jet
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