Re: Missing first index entry

[Gavin Smith]

On Tue, Feb 22, 2022 at 03:46:36PM +0300, Sergey Matveev wrote:
> run "makeinfo foo.texi" and info ./foo.info says that no indices found
> on "i"/"I" commands. If I rename "My" node to "My Index", then info
> won't note about missing indices. I did not find explicit note about
> that requirement.

We should add that to the manual.  This has always been the case.

> If I try to search "i foot<Enter>", then it finds "FOOTball" section and
> jumps to it as expected. But "i basket<Enter>" does not find anything.
> However "i basketball<Enter>" works as expected. "I ball<Enter>" shows
> only "football" entry. "I basket<Enter>" does not produce anything.
> "I foot<Enter>" works as expected.
> 
> When I tried to find how index entries are found and filled, I was sure
> that index_index variable is properly filled with two ("football",
> "basketball") entries.
> 
> I think that something wrong is going in next_index_match function with
> the cycles like: for (i = offset + dir; i > -1 && index_index[i]; i += dir)
> where offset=0, dir=1 and that means initial i's value is 1, so it "skips"
> the first entry in index_index.
> 
> If I add "@cindex aaa" (to be sure that it goes first after sort) before
> "@top foo", then all "i foot", "i bask", "I ball" work as expected.

Thanks for the report and investigation.  This definitely sounds like a
bug.  I'll look into it when I have time.