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From: Ken Brown <kbrown AT cornell DOT edu>
To: "cygwin AT cygwin DOT com" <cygwin AT cygwin DOT com>
CC: =?utf-8?B?UGV0ciBTa2/EjcOtaw==?= <pskocik AT gmail DOT com>
Subject: Re: malloc(0) crashing with SIGABRT
Date: Thu, 12 Sep 2019 16:12:36 +0000
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On 9/9/2019 1:13 PM, Petr Skočík wrote:
> There's been a twitter discussion on how different POSIX platforms
> handle malloc(0): https://twitter.com/sortiecat/status/1170697927804817412 .
> 
> As for Cygwin, the answer appears to be "not well", but this should be
> easy to fix.

Can you show how you produced a crash?  It works fine for me with the following 
test program:

$ cat malloc_zero.c
#include <stdlib.h>
#include <stdio.h>

int
main ()
{
   printf ("malloc (0) = %p\n", malloc (0));
}

$ gcc -Wall -o malloc_zero malloc_zero.c

$ ./malloc_zero.exe
malloc (0) = 0x8000003c0

[This is on 64-bit Cygwin.  It's the same on 32-bit, but with a different address.]

Ken

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