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From: "jvdelisle at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug fortran/56981] Slow I/O: Unformatted 5x slower, large sys component; formatted slow as well Date: Thu, 18 Apr 2013 01:21:00 -0000 [thread overview] Message-ID: <bug-56981-4-qpiAV1QqEF@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-56981-4@http.gcc.gnu.org/bugzilla/> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56981 --- Comment #6 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> 2013-04-18 01:21:42 UTC --- I like Jannes idea with the flags. Also, it seems that at the time we open a file we know it is /dev/null or /dev/nul in some cases by the file name. It would be very low overhead in a few cases to disable some or all checks and even disable the writing completely. We would not get all situations, but the low hanging fruit we could. It could be done by setting a "NULL" bit. One could consider doing this at compile time in some cases where the frontend could have more elaborate configuration checks that determine the name of the null device on the target system and look for its use. (probably not really worth if fur NULL I/O The other idea to consider is a compiler flag, say -fast-IO or similar that also disables the extra error checking that is not critical to runtime after a program has been debugged.
next prev parent reply other threads:[~2013-04-18 1:21 UTC|newest] Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top [not found] <bug-56981-4@http.gcc.gnu.org/bugzilla/> 2013-04-16 15:20 ` burnus at gcc dot gnu.org 2013-04-17 0:58 ` jvdelisle at gcc dot gnu.org 2013-04-17 10:50 ` jb at gcc dot gnu.org 2013-04-17 14:50 ` burnus at gcc dot gnu.org 2013-04-18 1:21 ` jvdelisle at gcc dot gnu.org [this message] 2013-04-19 10:34 ` jb at gcc dot gnu.org 2013-04-29 9:35 ` burnus at gcc dot gnu.org 2013-04-29 9:36 ` burnus at gcc dot gnu.org 2013-12-21 20:15 ` dominiq at lps dot ens.fr 2014-06-08 18:08 ` jvdelisle at gcc dot gnu.org 2014-06-08 23:57 ` jvdelisle at gcc dot gnu.org
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