Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!samsung!uunet!metaware!fjb
From: fjb@metaware.metaware.com (Fred Bourgeois)
Newsgroups: comp.lang.c
Subject: Re: scope of malloc
Summary: Wrong
Keywords: alloca
Message-ID: <650@metaware.metaware.com>
Date: 14 Nov 90 02:47:29 GMT
References: <3729@skye.ed.ac.uk> <14413@smoke.brl.mil> <3739@skye.ed.ac.uk> <14448@smoke.brl.mil>
Reply-To: fjb@metaware.UUCP (Fred Bourgeois)
Distribution: usa
Organization: MetaWare
Lines: 22

In article <14448@smoke.brl.mil> gwyn@smoke.brl.mil (Doug Gwyn) writes:
>In article <3739@skye.ed.ac.uk> richard@aiai.UUCP (Richard Tobin) writes:
>>Are there *any* widely-used processors that can't implement alloca()
>>reasonably efficiently even with compiler support?
>
>It can't be implemented correctly (except by the compiler turning it into
>malloc()/free() calls that you could have coded yourself) on any system
>that doesn't provide separate frame and stack pointers.  Just consider
>the effects of an interrupt.  It also cannot be reasonably implemented on
>a system that uses linked stack frames, such as on the IBM System/370.

You are Wrong.

Our compiler implements alloca() as an intrinsic, and does it correctly.

... even on the 370 ...

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Fred Bourgeois, MetaWare Inc., 2161 Delaware Avenue, Santa Cruz, CA 95060-2806
fjb@metaware.com					...!uunet!metaware!fjb
	     Colorless Green Ideas Sleep Furiously, and so do I.
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