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From: wallace@ynotme.enet.dec.com (Ray Wallace)
Newsgroups: comp.lang.c
Subject: Re: Nasty bug
Message-ID: <2020@engage.enet.dec.com>
Date: 30 Aug 90 15:15:38 GMT
Sender: news@engage.enet.dec.com
Organization: Digital Equipment Corporation
Lines: 23


In article <0093BF08.7F3834E0@rigel.efd.lth.se>, e89hse@rigel.efd.lth.se
writes... 
> I had a lot of trouble with a bug yesterday. The code was similar to the
>following:

>And it didn't work. Why? The answer is that the parameter f is a
>double, not a float since all floats are converted to double when they are
>passed as arguments to functions. Therefore &f is a ptr to double rather than a
>ptr to float as one would expect looking at the declartion.

Sounds like a compiler bug to me. Floats are promoted to double in a procedure
call but since your procedure declared the parameter as a float the compiler
should have "demoted" the parameter so that &variable would work properly.

FYI: Your code fragment worked properly with the VAX VMS-C compiler.

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