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From: gennadi.f@corigin.com To: gcc-gnats@gcc.gnu.org Subject: c/9902: optimization level -O2/3 doesn't work correctly. Date: Sun, 02 Mar 2003 16:26:00 -0000 [thread overview] Message-ID: <20030302162337.8219.qmail@sources.redhat.com> (raw) >Number: 9902 >Category: c >Synopsis: optimization level -O2/3 doesn't work correctly. >Confidential: no >Severity: serious >Priority: medium >Responsible: unassigned >State: open >Class: sw-bug >Submitter-Id: net >Arrival-Date: Sun Mar 02 16:26:00 UTC 2003 >Closed-Date: >Last-Modified: >Originator: gennadi.f@corigin.com >Release: 3.2.2 >Organization: >Environment: sunOS 2.8 sparc >Description: #include <stdio.h> #include <string.h> #include <stdlib.h> int main() { char *page,*p; page=calloc(1,4); page+=4; p=page; if (page) { // if we change "page" here to "1", the result will be correct *((char **)page-1)=page; // save the address in its previous 4 bytes. (*((char ***)page-1))++; // add 4 to the saved address. } page=*((char **)page-1); //"page" should be assigned to the new value. printf("page=%08X p=%08X\n",page,p); // with the optimization level -O2/3, the value of page i s not changed. return 0; } >How-To-Repeat: compile with and without O3/O2 options. >Fix: >Release-Note: >Audit-Trail: >Unformatted:
next reply other threads:[~2003-03-02 16:26 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2003-03-02 16:26 gennadi.f [this message] 2003-03-02 16:43 paolo 2003-03-02 17:03 paolo 2003-03-14 15:48 ebotcazou
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