From: utzoo!decvax!harpo!npoiv!npois!cbosgd!mark
Newsgroups: net.unix-wizards
Title: Re: please fix floating point in the c compilers!
Article-I.D.: cbosgd.2605
Posted: Wed Sep  8 12:15:46 1982
Received: Thu Sep  9 05:37:56 1982
References: sri-unix.3116

I quote from page 184 of the C book (section 6.2 of the C reference
manual):

"All floating arithmetic in C is carried out in double-precision;
whenever a float appears in an experssion it is lengthened to double
by zero-padding its fraction."

Thus, any "fix" to the C compilers that cause single precision arithmetic
to be carried out using single precision instructions would be a
violation of the language, unless it could be shown that the results
would be identical.

I will not attempt to defend this, since I rarely use floating point
I don't care one way or the other.  But this property has been with
the language since day one and is unlikely to change in the near future.

Note that a similar thing happens with char/short/int - everything is
widened to int before anything is done.  Nobody seems to mind this,
although if everything were widened to long on an 11 I suspect people would.