Re: Uh-oh: documentation PDF output no longer builds in HEAD

On Mon, Nov 9, 2015 at 7:46 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> I wrote:
>> Curiously though, that gets us down to this:
>> 30615 strings out of 245828
>> 397721 string characters out of 1810780
>> which implies that indeed FlowObjectSetup *is* the cause of most of
>> the strings being entered. I'm not sure how that squares with the
>> observation that there are less than 5000 \pagelabel entries in the
>> postgres-US.aux file. Time for more digging.
>
> Well, after much digging, I've found what seems a workable answer.
> It turns out that the original form of FlowObjectSetup is just
> unbelievably awful when it comes to handling of hyperlink anchors:
> it will put a hyperlink anchor into the PDF for every "flow object",
> that is, everything in the document that could possibly have a link
> to it, whether or not it actually is linked to. And aside from bloating
> the PDF file, it turns out that the hyperlink stuff also consumes some
> control sequence names, which is why we're running out of strings.
>
> There already is logic (probably way older than the hyperlink code)
> in jadetex to avoid generating page-number labels for objects that have
> no cross-references. So what I did to fix this was to piggyback on
> that code: with the attached jadetex.cfg, both a page-number label
> and a hyperlink anchor will be generated for all and only those flow
> objects that have either a page-number reference or a hyperlink reference.
> (We could try to separate those things, but then we'd need two control
> sequence names not one per object for tracking purposes, and anyway many
> objects will have both kinds of reference if they have either.)
>
> This gets us down to ~135000 strings to build HEAD, and not incidentally,
> the resulting PDF is about half the size it was before. I think I've
> also fixed a number of formerly unexplainable broken hyperlinks in the
> PDF; some are still broken, but they were that way before. (It looks
> like <xref> with endterm doesn't work very well in jadetex; all the
> remaining bad links seem to be associated with uses of that.)
>
> Barring objection I'll commit this tomorrow. I'm inclined to back-patch
> it at least into 9.5, maybe further, because I'm afraid we may be closer
> than we realized to exceeding the strings limit in the back branches too.

I am in awe.

--
Robert Haas
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