Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!rutgers!mit-eddie!uw-beaver!sumax!amc-gw!nwnexus!pilchuck!dataio!bright
From: bright@Data-IO.COM (Walter Bright)
Newsgroups: comp.lang.c++
Subject: Re: Zortech Problem: heap corrupted
Message-ID: <2630@dataio.Data-IO.COM>
Date: 10 Aug 90 18:20:07 GMT
References: <24059.26BA6CC2@stjhmc.fidonet.org> <2613@dataio.Data-IO.COM> <ROGER.90Aug9091458@rd11.zuken.co.jp>
Organization: Data I/O Corporation; Redmond, WA
Lines: 19

In article <ROGER.90Aug9091458@rd11.zuken.co.jp> roger@zuken.co.jp (Roger Meunier) writes:
<In article <2613@dataio.Data-IO.COM> bright@Data-IO.COM (Walter Bright) writes:
< <Try this program with your favorite C compiler:
< <	  #include <stdlib.h>
< <	  main()
< <	  {	char *p;
< <		  p = (char *) malloc(10);
< <		  free(p);
< <		  free(p);
< <	  }
< <With Zortech, you'll get a "Heap is corrupted" message on the second free.
< <With some other compilers, you'll get silence, but this does not mean
< <that the program worked.
<There should be a clear distinction in your comments as to what the
<compiler does and what the *run-time library* does.  In your example,
<it's not clear if the compiler catches the second free or if the library
<routine does.

The library does this. The compiler knows nothing about malloc or free.