From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Tolpin <dvd@davidashen.net>
Message-Id: <200403042354.i24Ns8tA073468@adat.davidashen.net>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] fp stack overflow -- hypot
In-Reply-To: <02bb01c40244$20a2ac20$8201a8c0@cc77109e>
Content-Type: text/plain; charset=KOI8-R
Date: Fri,  5 Mar 2004 03:54:08 +0400
Topicbox-Message-UUID: 15cf9a28-eacd-11e9-9e20-41e7f4b1d025

> ok, i've found the problem.  take a look in:
>
> /386/include/ape/math.h
>
> and you'll see that hypot() is not declared unless
>
> _RESEARCH_SOURCE is.
>
> hence the compiler presumes that the function returns
> int and picks up AX rather than popping the fp stack.
>
> solution: either define _RESEARCH_SOURCE, or if
> that introduces conflicts then simply copy the prototype
> from math.h to somewhere visible.
>
> it may really be a "faulty", in the posix sense, math.h
> but i'm avoiding investigating that.

Yes, you are right, I am wrong, I wrote about it to the list;
my apologies. hypot is not POSIX.

I just didn't realize that, unlike pcc, cc does not issue warnings
by default.

David