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From: "ian at airs dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/52571] New: vectorizer changes alignment of common symbols Date: Mon, 12 Mar 2012 21:53:00 -0000 [thread overview] Message-ID: <bug-52571-4@http.gcc.gnu.org/bugzilla/> (raw) http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52571 Bug #: 52571 Summary: vectorizer changes alignment of common symbols Classification: Unclassified Product: gcc Version: 4.7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization AssignedTo: unassigned@gcc.gnu.org ReportedBy: ian@airs.com Compile this file with current mainline with -O2 on an ELF system: unsigned long int *p; void f (char **a) { p = (unsigned long int *) a; } In the .s file I see this: .comm p,8,8 Now compile it with -O3. In the .s file I see this: .comm p,8,16 The alignment of a common symbol should not change based on the compiler optimization level. This appears to happen in vect_compute_data_ref_alignment. Perhaps vect_can_force_dr_alignment_p needs to check DECL_COMMON.
next reply other threads:[~2012-03-12 21:53 UTC|newest] Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top 2012-03-12 21:53 ian at airs dot com [this message] 2012-03-12 22:10 ` [Bug tree-optimization/52571] " pinskia at gcc dot gnu.org 2012-03-13 8:35 ` rguenth at gcc dot gnu.org 2012-03-13 17:12 ` ian at airs dot com 2012-03-14 9:39 ` rguenther at suse dot de 2012-03-14 13:02 ` rguenth at gcc dot gnu.org 2012-03-14 13:02 ` rguenth at gcc dot gnu.org 2012-03-16 16:49 ` rguenth at gcc dot gnu.org 2012-03-20 15:33 ` ro at gcc dot gnu.org 2012-03-20 15:57 ` dominiq at lps dot ens.fr 2012-03-20 16:03 ` dominiq at lps dot ens.fr 2012-04-09 23:54 ` mrs at gcc dot gnu.org 2012-05-10 11:45 ` rguenth at gcc dot gnu.org 2012-05-10 12:15 ` jakub at gcc dot gnu.org 2012-05-10 16:11 ` mrs at gcc dot gnu.org
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