Re: Macro nesting hell

Tom Lane wrote:
> Last night my ancient HP compiler spit up on HEAD:
> http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=pademelon&dt=2015-07-01%2001%3A30%3A18
> complaining thus:
> cpp: "brin_pageops.c", line 626: error 4018: Macro param too large after substitution - use -H option.
> I was able to revive pademelon by adding a new compiler flag as suggested,
> but after looking at what the preprocessor is emitting, I can't say that
> I blame it for being unhappy. This simple-looking line
>
> Assert(BRIN_IS_REGULAR_PAGE(BufferGetPage(oldbuf)));
>
> is expanding to this:

Wow, that's kind of amazing. I think this particular case boils down to
just PageGetSpecialPointer (bufpage.h) and BufferGetBlock (bufmgr.h).

> I'm thinking we really ought to mount a campaign to replace some of these
> macros with inlined-if-possible functions.

My guess is that changing a very small amount of them will do a large
enough portion of the job.

--
Álvaro Herrera http://www.2ndQuadrant.com/
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