Xref: utzoo comp.sys.ibm.pc:10048 comp.lang.c:5925
Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!lll-tis!ames!hao!husc6!rutgers!mtune!lzaz!lznv!psc
From: psc@lznv.ATT.COM (Paul S. R. Chisholm)
Newsgroups: comp.sys.ibm.pc,comp.lang.c
Subject: Re: BUG in Turbo C v1.0 float ???
Message-ID: <1241@lznv.ATT.COM>
Date: 31 Dec 87 17:32:26 GMT
References: <1304@phoenix.Princeton.EDU>
Organization: AT&T
Lines: 31
Keywords: Turbo C, Bug, float, parameter passing
Summary: ancient float/double bug; patched in 1.0, fixed in 1.5

In article <1304@phoenix.Princeton.EDU>, asjoshi@phoenix.Princeton.EDU (Amit S. Joshi) writes:
> #include <sdtio.h>
> #define reals float
> main() {
> 	reals c;
> 	
> 	c = -3.0;
> 	print_f(c);
> }
> print_f(c)
> reals c;{
> 	printf("%f\n",c);
> }

Okay, one last time.  There was a problem with functions that took
float (not double) arguments in early versions of TC 1.0.  The actual
argument (in the call) was cast to double, as per K&R, but the formal
argument (in the function definition) wasn't.  (Or maybe the other way
around.  Doesn't matter.)  No problem if you used doubles, or ANSI/C++
style function prototypes or definitions:
	print_f( float c)

If you have an older copy of 1.0, you can get a patch from Borland.
(The patch was on the net, too.)  However, this bug is just plain fixed
in my real, live, non-beta copy of TC 1.5, which is pretty nice anyway.
1.5 has just about everything 1.0 users asked for (except a
debugger:-), and then some.  I'll post comments on 1.5 when I have a
chance.  (Don't hold your breath.)

-Paul S. R. Chisholm, {ihnp4,cbosgd,allegra,rutgers}!mtune!lznv!psc
AT&T Mail !psrchisholm, Internet psc@lznv.att.com
I'm not speaking for my employer, I'm just speaking my mind.