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Article #42021Query on malloc 2.6.3
From: Carlos da Roza
Date: Tue, 16 Jan 1996 00:00
Date: Tue, 16 Jan 1996 00:00
24 lines
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1663 bytes
Under gcc 2.6.3, I'm reaching a condition where I'm getting segment faults on a malloc (no switches on gcc). Compiled under level 3 debug (gdb) and executed, at the point of the segmentation fault, the back trace shows a call into __gcc_malloc, which calls _malloc. When I try a "print malloc(7)", it faults, as it does with any value less than, say 9. Thus "print malloc(7)" yields a segmentation fault, while a "print malloc(9)" works. I figure I've corrupted heap somewhere, so I slowly step through the code from the beginning. At one point in the code (before the segmentation fault), I do two mallocs, one after the other, with valid positive arguments. The returns are queer...they are identical and seem to be large values (e.g. 0x1ff78). The question is: Is there a location I can go to look up debug problems like this? By the way, it does compile and execute clean under MS Visual C, although I am aware that there are some differences...I believe I've avoided the issues of constant strings (can be overwritten in MSC, not in gcc), and a check for NULL returns on malloc. Thanks, Carlos da Roza daroza@cn.ca
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X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 11318c,46d01393105ecdf3,start X-Google-Attributes: gid11318c,public From: Carlos da Roza <daroza@cn.ca> Subject: Query on malloc 2.6.3 Date: 1996/01/16 Message-ID: <30FB5842.40B9@cn.ca> X-Deja-AN: 135387387 sender: usenet@goshawk.cn.ca (news) cc: daroza@cn.ca content-type: text/plain; charset=us-ascii organization: Canadian National Railways mime-version: 1.0 newsgroups: gnu.gcc.help x-mailer: Mozilla 2.0b3 (Win95; I)