bug#9990: valgrind warning in add_row_entry

[Dan Nicolaescu]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Dan Nicolaescu <dann@gnu.org>
>> Cc: 9990@debbugs.gnu.org
>> Date: Fri, 11 Nov 2011 15:20:19 -0500
>> 
>> I haven't seen the one in row_equal_p anymore (but that one was not easy
>> to reproduce), the ones in update_window still show up.
>
> I added a function that verifies the hash value of glyph rows before
> it is used in row_equal_p, and also in adjust_glyph_matrix, where the
> offending reallocation takes place.  I cannot trigger the xasserts
> that use this function when I use "C-h H".  Can you?

BTW, why is the hash only using 28 bits instead of the full 32?  Won't
it get a bit more precision if using 32?