[cxx-abi-dev] There is no obligation to unique virtual tables

[Jason Merrill]

On 02/18/2013 01:12 PM, John McCall wrote:
>> we decided that it was too expensive to use for _ZTSs, so we left them only mostly unique
>
> So... _ZTSs are less unique now than they were before. :)

Exactly as unique as they were before; that is, unique except in the 
presence of RTLD_LOCAL.  We just declined to use the new technology to 
make them even more unique.

>> For types local to a translation unit we still do pointer comparison.
>
> Out of curiosity, do you try to use pointer comparison for types with hidden visibility, or is it just internal vs. at-any-visibility external?

Just internal; for them, string comparison could mistakenly decide that 
two unrelated types are the same.

Jason