From owner-freebsd-hackers Wed Apr 29 13:20:29 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id NAA20045 for freebsd-hackers-outgoing; Wed, 29 Apr 1998 13:20:29 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from symbion.srrc.usda.gov ([199.78.118.118]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id NAA19705 for ; Wed, 29 Apr 1998 13:19:58 -0700 (PDT) (envelope-from glenn@nola.srrc.usda.gov) Received: from nola.srrc.usda.gov (localhost.srrc.usda.gov [127.0.0.1]) by symbion.srrc.usda.gov (8.8.8/8.8.8) with ESMTP id PAA03017 for ; Wed, 29 Apr 1998 15:19:38 -0500 (CDT) (envelope-from glenn@nola.srrc.usda.gov) Message-Id: <199804292019.PAA03017@symbion.srrc.usda.gov> X-Mailer: exmh version 2.0.2 2/24/98 To: hackers@FreeBSD.ORG From: Glenn Johnson Subject: debugging Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 29 Apr 1998 15:19:38 -0500 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG I sent the message below to questions@freebsd.org a few days ago but have not received a response so I thought I would try here. Thanks. -------------------------------- I have some Fortran programs that compile and run fine using f77 (f2c/cc). If I compile the code with g77 I get significantly better performance but some of the programs will give the following message upon completion: free(): warning: modified (page-) pointer I get the correct results from the programs but I am concerned. How serious of a problem is this? Am I correct in assuming that g77 is optimizing the code in a way that is exposing a bug in the program code? Since using gdb on g77 compiled code is less than ideal, does anyone have an idea on how to go about finding info on the problem(s)? I am not a skilled programmer but I would like to be able to provide information to the program developers. The malloc warning does not occur under Linux/g77 and so they may not be aware of any underlying bug(s). Thanks in advance for your help. -- Glenn Johnson Technician USDA-ARS-SRRC Phone: (504) 286-4252 1100 Robert E. Lee Boulevard FAX: (504) 286-4217 New Orleans, LA 70124 e-mail: gjohnson@nola.srrc.usda.gov To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message