BUG #15039: some question about hash index code

The following bug has been logged on the website:

Bug reference: 15039
Logged by: lixian zou
Email address: zoulx1982(at)163(dot)com
PostgreSQL version: 10.0
Operating system: source code
Description:

hi,
i read hash index code , and found in _hash_addovflpage function, there is
such code :
if (metap->hashm_firstfree == orig_firstfree)
{
metap->hashm_firstfree = bit + 1;
MarkBufferDirty(metabuf);
}

i found no any chang for metap,metap->hashm_firstfree,and initial the two
variable is equal, so maybe the if statement is redundant?

thanks.