Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!usc!zaphod.mps.ohio-state.edu!uakari!aplcen!uunet!oresoft!dan
From: dan@oresoft.uu.net (Daniel Elbaum)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Manx 5.0 problems
Message-ID: <1990Feb24.005652.971@oresoft.uu.net>
Date: 24 Feb 90 00:56:52 GMT
References: <35312@grapevine.EBay.Sun.COM>
Reply-To: dan@oresoft.uu.net (Daniel Elbaum)
Organization: Oregon Software, Portland, OR
Lines: 34

In article <35312@grapevine.EBay.Sun.COM> golson@grapevine.EBay.Sun.COM (Greg Olson) writes:
:Hi everyone.  I've been using Manx 5.0 for a little while, and thought I'd 
:post a few problems I've run across.

[a few problems]

:	3) (Probably the most frustrating)  It seems that Manx doesn't handle
:	using new style prototyping and old style function definition parameter
:	promotion correctly.  For instance:
:
:		int test_func(int);	/* HAS TO BE INT FOR ANSI */
:		main(){test_func('X');}
:		int test_func(y)
:		char y;
:		{ printf("X = %c\n",y); }
:
:	will not print X to the screen (as it should, by my understanding of
:	ANSI promotion rules for new-style prototype/old style function
:	definitions).
:
:I have a few mail messages into Manx, but haven't heard word one as of yet.
:Can anyone verify/dispute these?

You give test_func an int, but it only takes a char.  The prototype
for test_char() does not specify any conversion to int to be
performed at the point of the call.  So an int gets passed, and part
of that int is what y refers to.  There's never a guarantee that
mixing declaration styles as in this example will work the way you
expect.  The danger is that sometimes it will.

-- 
Mine is red, round, and has three buttons.  --B. Stroustrup

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