Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!wuarchive!zaphod.mps.ohio-state.edu!rpi!uupsi!sunic!tut!funic!santra!hutcs.hut.fi!jaa
From: jaa@hutcs.hut.fi (Jari Alasuvanto)
Newsgroups: comp.lang.c++
Subject: Re: Zortech Problem: heap corrupted
Message-ID: <1990Aug3.060516.7577@santra.uucp>
Date: 3 Aug 90 06:05:16 GMT
References: <2353@laura.UUCP> <2605@dataio.Data-IO.COM>
Sender: news@santra.uucp (Cnews - USENET news system)
Organization: Helsinki University of Technology, Finland
Lines: 31

In article <2605@dataio.Data-IO.COM> bright@Data-IO.COM (Walter Bright) writes:
>
>The "heap is corrupted" message is generated by the free() function under
>the following conditions:

<A list of conditions deleted>

>A common source of this error in C++ programs is when the compiler generates
>a default copy constructor, and the objects contain pointers to malloc'd
>data. (It's not a compiler bug!)

I would add one common one to the list: a bug in your code using
strings (applies to C as well):
	void causeError( const char* aString) {
		char* tmp = new char[ strlen(aString) ] ;
				// OOPS, forgot to add one for
				// terminating null
		strcpy ( tmp, aString ) ;
	}

Errors of this kind will most likely go unnoticed for Motorola based
machines and SPARCs, but with Intel-based architecture, the heap gets
corrupted.  This is due to different byte ordering.  Check your code
first before the compiler.


--
Jari Alasuvanto, Lab. of Info Proc. Sci, Helsinki Univ. of Techology, Finland
Internet: jaa@hutcs.hut.fi
tel: 	+358-0-451 3236 	fax:  +358-0-465 077
<All the statements are my own -- HUT can make its own>>