`declare-function' and compiler warnings.

`declare-function' and compiler warnings.

[Jay Belanger]

I recently noticed that compiling `calc.el' results in a compiler
warning: "the function `math-zerop' is not known to be defined".
(I can fix that when I get to my home computer.)

The function `math-zerop' is not explicitly used in calc.el, but it
does appear in the bytecode since it is part of the definition of the
inline function `Math-zerop' which is used in calc.el.
Is there supposed to be a compiler warning in this case?
It turns out that `math-zerop' is used explicitly in other files with
no declaration and no compiler warning (because it is autoloaded,
perhaps). 

Finally, there is no declaration for `Math-zerop' in calc.el and no
warning, either.  In the elisp info file, "Declaring Functions", it
mentions explicitly how to handle functions defined with `defstruct' (as
`Math-zerop' is), so I would expect a declaration would be necessary.
Should it be?

I am probably missing some subtleties of when declaring functions is
necessary; I'll be happy just declaring them when I see compiler
warnings.

Jay

Re: `declare-function' and compiler warnings.

[Andreas Schwab]

Jay Belanger <jay.p.belanger@gmail.com> writes:

> I recently noticed that compiling `calc.el' results in a compiler
> warning: "the function `math-zerop' is not known to be defined".

Doesn't happen for me.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
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Re: `declare-function' and compiler warnings.

[Glenn Morris]

Jay Belanger wrote:

> I recently noticed that compiling `calc.el' results in a compiler
> warning: "the function `math-zerop' is not known to be defined".

I also can't reproduce this. AFAICS, there are no compiling warnings
when bootstrapping any calc files, so I don't think you have anything to
worry about.

Since as you say math-zerop is autoloaded, I don't see how you can get
this warning. Perhaps you happened to compile with an incomplete/messed
up calc-loaddefs.el. Unless you can reproduce in a clean build I would
forget about it.

Re: `declare-function' and compiler warnings.

[Jay Belanger]

Glenn Morris <rgm@gnu.org> writes:

>> I recently noticed that compiling `calc.el' results in a compiler
>> warning: "the function `math-zerop' is not known to be defined".
>
> I also can't reproduce this.

Thanks for checking this.  (You too, Andreas.)

> Since as you say math-zerop is autoloaded, I don't see how you can get
> this warning. Perhaps you happened to compile with an incomplete/messed
> up calc-loaddefs.el.

I got the warning consistently on my other computer, but I just tried it
on a different computer with no warning.  (Up to date checkouts on both
computers.)  So I will take your advice and

> Unless you can reproduce in a clean build I would forget about it.