From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <02bb01c40244$20a2ac20$8201a8c0@cc77109e>
From: "Bruce Ellis" <brucee@chunder.com>
To: <9fans@cse.psu.edu>
References: <200403042218.i24MIRFI059560@adat.davidashen.net>
Subject: Re: [9fans] fp stack overflow -- hypot
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Date: Fri,  5 Mar 2004 10:53:47 +1100
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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.

brucee
----- Original Message ----- 
From: "David Tolpin" <dvd@davidashen.net>
To: <9fans@cse.psu.edu>
Sent: Friday, March 05, 2004 9:18 AM
Subject: [9fans] fp stack overflow -- hypot

> The offending function is hypot(2). If I replace it with sqrt(p*p+q*q),
> no more stack overflows no matter what are shapes and how complex the graph
> is.
> 
> I think it is a compiler bug. But need more time or someone's help.
> 
> David