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From: "fxcoudert at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug fortran/34128] slow gfortran 4.x (library?) compared to g77 3.4 Date: Sat, 17 Nov 2007 00:08:00 -0000 [thread overview] Message-ID: <20071117000755.26839.qmail@sourceware.org> (raw) In-Reply-To: <bug-34128-15355@http.gcc.gnu.org/bugzilla/> ------- Comment #1 from fxcoudert at gcc dot gnu dot org 2007-11-17 00:07 ------- While I'm trying to understand what happens, I should say that a simply workaround is to make your calculation happen in double precision (change "3.14159" into "3.14159d0"; after all, you want a double-precision result). g77 called sin() to perform the calculation, while gfortran calls sinf(). And sinf() happens to be way slower than sin() (I wonder why!). Maybe a bugreport to glibc will be in order here. -- fxcoudert at gcc dot gnu dot org changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |fxcoudert at gcc dot gnu dot | |org Status|UNCONFIRMED |NEW Component|libfortran |fortran Ever Confirmed|0 |1 Keywords| |missed-optimization Last reconfirmed|0000-00-00 00:00:00 |2007-11-17 00:07:55 date| | http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34128
next prev parent reply other threads:[~2007-11-17 0:08 UTC|newest] Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top 2007-11-16 22:23 [Bug libfortran/34128] New: " mnoble at space dot mit dot edu 2007-11-17 0:08 ` fxcoudert at gcc dot gnu dot org [this message] 2007-11-17 22:35 ` [Bug fortran/34128] " bdavis at gcc dot gnu dot org 2007-11-17 22:42 ` fxcoudert at gcc dot gnu dot org 2007-11-18 8:37 ` burnus at gcc dot gnu dot org 2007-12-08 19:00 ` jvdelisle at gcc dot gnu dot org 2007-12-08 19:05 ` jvdelisle at gcc dot gnu dot org 2008-03-29 4:49 ` jvdelisle at gcc dot gnu dot org 2008-03-29 5:28 ` jvdelisle at gcc dot gnu dot org 2008-03-29 21:20 ` jvdelisle at gcc dot gnu dot org 2009-03-28 13:21 ` fxcoudert at gcc dot gnu dot org
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