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From: khb%chiba@Sun.COM (Keith Bierman - SPD Advanced Languages)
Newsgroups: comp.lang.c,comp.sys.super
Subject: Re: Type punning in C
Message-ID: <126279@sun.Eng.Sun.COM>
Date: 13 Oct 89 01:10:32 GMT
References: <475@idacrd.UUCP> <1989Oct10.185851.6490@agate.berkeley.edu> <1989Oct11.091619.18336@gdt.bath.ac.uk>
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Reply-To: khb@sun.UUCP (Keith Bierman - SPD Advanced Languages)
Organization: Sun Microsystems, Mountain View
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In article <1989Oct11.091619.18336@gdt.bath.ac.uk> exspes@gdr.bath.ac.uk (P E Smee) writes:


>Problem is, the Fortran standard *also* says that if your program tries
>to take the value of the variable using a different type than the type you
>used when you last stored into it, your program is invalid.  This is a
>polite way of saying (to the user) 'this trick may not work', and (to
>the

My quick peek into the document (pages 8-3 and 17-1..4ish) doesn't
make this obvious to me. Could you please quote chapter and verse ?

>
>Fortran equivalence was designed toallow reuse of storage on the early
>small memory machines -- not to allow type punning.  Usually you can
>get away with punning, but it doesn't always work and so is a bad habit.
>

On which systems (if any) have you seen this not work ?


Keith H. Bierman    |*My thoughts are my own. !! kbierman@sun.com
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