X-Spam-Check-By: sourceware.org Date: Tue, 6 Mar 2007 22:23:22 -0800 From: Gary Johnson To: cygwin@cygwin.com Subject: Re: [Testcase] Memory returned by malloc not always zeroed. Message-ID: <20070307062322.GA21235@suncomp1.spk.agilent.com> Mail-Followup-To: cygwin@cygwin.com References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.12 (2006-07-14) X-IsSubscribed: yes Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Delivered-To: mailing list cygwin@cygwin.com On 2007-03-07, Buzz wrote: > Hi, > > On three different cygwin 1.5.24-2 systems, attached testprogram > (compile with ``gcc -o mall-test mall-test.c'') > returns many lines like: > > n1 S13 p12 is 0x81, not 0 > n1 S14 p0 is 0x8c, not 0 > n1 S14 p1 is 0x7f, not 0 > n1 S14 p2 is 0x14, not 0 > n1 S14 p3 is 0x61, not 0 > n1 S14 p4 is 0x8c, not 0 > n1 S14 p5 is 0x7f, not 0 > n1 S14 p6 is 0x14, not 0 > n1 S14 p7 is 0x61, not 0 > n1 S14 p12 is 0x81, not 0 > > This indicates malloc returning non-zeroed memory. > > Has anybody got a clue as to what's going on? Malloc() returns a pointer to a block of memory. Other than size and alignment, the contents of that memory is not specified. If you want a block of memory initialized to zero, use calloc(). Regards, Gary -- Gary Johnson | Agilent Technologies garyjohn@spk.agilent.com | Mobile Broadband Division | Spokane, Washington, USA -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/