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Path: utzoo!utcsri!greg
From: greg@utcsri.UUCP (Gregory Smith)
Newsgroups: net.lang.c
Subject: Float Double Parameters
Message-ID: <2442@utcsri.UUCP>
Date: Tue, 1-Apr-86 03:17:22 EST
Article-I.D.: utcsri.2442
Posted: Tue Apr  1 03:17:22 1986
Date-Received: Tue, 1-Apr-86 03:42:36 EST
References: <2600042@ccvaxa> <5216@alice.uUCp>
Reply-To: greg@utcsri.UUCP (Gregory Smith)
Organization: CSRI, University of Toronto
Lines: 30
Summary: 

In article <5216@alice.uUCp> ark@alice.UucP (Andrew Koenig) writes:
>>X3J11 says "arguments that have type float are promoted to double". Too bad.
>
>Ansi C also lets you declare types of formal parameters to externals:
>
>	extern float f(float x);
>in which case:
>	f(1);		/* 1 is converted to float */
>	f(1.0);		/* 1.0 is converted to float */
>
>are both OK.

OK, but doesn't "extern float f(float x)" really mean
"extern float f( double x )"?  I.e. '1' and '1.0' are passed as doubles to
f in the above examples. I don't know, but I suppose this feature has been
added only to allow the compiler to check ( and convert when applicable ) the
parameter types.

If the above *is* correct, then apparently I can pass a float to a function
( provided it is not defined in the current file (!?!?!?!) ) but it is *not*
possible to write a function that accepts a float as a parameter.

C is strange, but not that strange - I suspect Mr. Koenig has read something
into the standard that is not there.  If anyone has reliable information
to the contrary, let us know...

-- 
"If you aren't making any mistakes, you aren't doing anything".
----------------------------------------------------------------------
Greg Smith     University of Toronto      UUCP: ..utzoo!utcsri!greg