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From: jerry@violet.berkeley.edu ( Jerry Berkman )
Newsgroups: comp.lang.c,comp.sys.super
Subject: Re: Type punning in C
Message-ID: <1989Oct10.185851.6490@agate.berkeley.edu>
Date: 10 Oct 89 18:58:51 GMT
References: <475@idacrd.UUCP>
Sender: usenet@agate.berkeley.edu (USENET Administrator;;;;ZU44)
Reply-To: jerry@violet.berkeley.edu ( Jerry Berkman )
Organization: University of California, Berkeley
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In article <475@idacrd.UUCP> desj@idacrd.UUCP (David desJardins) writes:
>   Does anyone have any ideas on how one should go about converting an
>integer to the floating-point number with the same bit pattern?
>The best way I have found to do this in FORTRAN is to write

>      INTEGER I
>      REAL X
>      X = OR (I, 0).

>(The Cray FORTRAN compiler optimizes out the trivial OR instruction.)
>   -- David desJardins

Why not use equivalence?
	INTEGER I
	REAL X, IX
	EQUIVALENCE (X,IX)

	IX = I
The Fortran standard specifies that a REAL and INTEGER occupy the same space.
The only problem is this might fool some optimizers.

	- Jerry Berkman
	  jerry@violet.berkeley.edu