Path: utzoo!utgpu!watmath!uunet!tut.cis.ohio-state.edu!UUNET.UU.NET!mcvax!moncam!paul
From: mcvax!moncam!paul@UUNET.UU.NET (Paul Hudson)
Newsgroups: gnu.gcc.bug
Subject: Small floating point constants are doubles?
Message-ID: <8903221553.AA04823@marvin.moncam.uucp>
Date: 22 Mar 89 15:53:03 GMT
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A small floating point constant in gcc has type double. This can cause unwanted promotions
of other objects to doubles, like

float h()
{
	float f;
	...
	return f * 2.0;
}

as a trivial example. This has an "unnecessary" promotion of f to double, and a shortening to
float again on the return. It would be nice if sufficiently small/imprecise constants could
be of float type at least as an option, if not by default.

Not having an up-to-date ANSI C draft to hand I can't say whether this is allowed by the standard.
but it would be useful!

Paul Hudson 

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