Re: Certain numbers of special forms cause changing behaviour on function calls in --batch

[Eli Zaretskii <eliz@gnu.org>]

> From: Noam Postavsky <npostavs@users.sourceforge.net>
> Date: Sun, 10 Jul 2016 07:33:47 -0400
> Cc: Eli Zaretskii <eliz@gnu.org>, Michael Heerdegen <michael_heerdegen@web.de>, me@wilfred.me.uk, 
> 	Emacs developers <emacs-devel@gnu.org>
> 
> I have gcc 5.3.0 here, and I get 10 (correct) when I compile Emacs
> 24.5 configured with --enable-checking, but 20 (incorrect) without
> that flag.

I've just built 24.5 with GCC 5.3.0 and without --enable-checking, and
I still don't see the problem in the resulting binary.

> In both cases running temacs with valgrind gives some
> errors which look suspicious (the version without --enable-checking
> additionally gives a bunch of what I assume are false positives while
> starting up). Emacs 25 gives similar errors (I haven't tried Emacs 25
> without --enable-check).
> 
> (I'm showing here just the results from the --enable-checking
> versions, without it's the same except for printing 20 instead of 10)
> 
> valgrind emacs-24.5/src/temacs -Q --batch -l nasty-move-end-of-line-batch.el
> [...]
> ==6167== Conditional jump or move depends on uninitialised value(s)
> ==6167==    at 0x55E74E: CHECK_NUMBER_OR_FLOAT (lisp.h:2627)
> ==6167==    by 0x5EC762: Fzerop (data.c:2387)

I don't understand these errors.  Please show the macro-expanded
source of Fzerop with that compiler and configuration options.