malloc_debug question

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#1527

From: Mike Carlton
Date: Thu, 15 Oct 1992 19:11

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I'm trying to track down a malloc() bug in one of my programs and have a
question about malloc_debug().

If I turn on debugging with malloc_debug(15) my program dies eventually 
when I am calling calloc(), with the error:
	**Bad free area not marked free
	Malloc corrupted entering malloc

My question is what the heck is this error supposed to mean?  Did I free
a block that wasn't allocated by malloc?  Did I write past the end of a
malloc'ed block and munge the header of a free block?  Or did I look at
the console cross-eyed?  BTW, this error isn't generated if I run with
only malloc_debug(7).

Once I figure out what went wrong, maybe I can track down the actual
bug.

cheers,
--mike (carlton@cs.berkeley.edu)

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From: carlton@cs.berkeley.edu (Mike Carlton)
Newsgroups: comp.sys.next.programmer
Subject: malloc_debug question
Date: 15 Oct 1992 19:11:58 GMT
Organization: University of California, Berkeley
Lines: 19
Distribution: world
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