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Re: Fourth Draft "Unsafe fp optimizations" project description.
- To: lucier at math dot purdue dot edu (Brad Lucier)
- Subject: Re: Fourth Draft "Unsafe fp optimizations" project description.
- From: Joe Buck <jbuck at synopsys dot COM>
- Date: Wed, 15 Aug 2001 18:25:10 -0700 (PDT)
- Cc: dewar at gnat dot com, lucier at math dot purdue dot edu, syedali011 at earthlink dot net, ejr at cs dot berkeley dot edu, gcc at gcc dot gnu dot org, kaih at khms dot westfalen dot de
> > <<test.c:4: warning: comparing floating point with == or != is unsafe
> > >>
> >
> > This is an annoying warning, because it is nonsense.
>
> For what it's worth, I agree with you. But some people's nonsense is
> other people's sense, and it isn't invoked by any other "group"
> warning flag, like -W or -Wall, so if people want it, they can have it.
> I don't want it, and I don't specify -Wfloat-equal, and I don't get it.
Provided that the warning is never added to -Wall, and provided that the
text is changed (for example, to "may be unsafe", which is more accurate),
it's OK with me. It may be useful to request the compiler to flag these
operations.
But a warning should never be added to -Wall if it will direct the
maintainer of a program to make it less efficient (or else live with
the warning).