http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54141
Bug #: 54141 Summary: The optimizer -O produces a bug. Classification: Unclassified Product: gcc Version: 4.8.0 Status: UNCONFIRMED Severity: critical Priority: P3 Component: fortran AssignedTo: unassig...@gcc.gnu.org ReportedBy: alain.heb...@polymtl.ca Created attachment 27907 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27907 untar with tar xvfzp bug.tgz The use of "-O" produces a bug. I was able to reproduce the bug on a simple test case. Removing "-O" makes everything OK, but CPU times on our software are 3 time bigger. Removing "-O" is therefore not acceptable to us. The bug was observed on Darwin, (mac os 10.8), but all our UBUNTU users have the same problem. Here is the faulty output from our test case: Alains-MacBook-Pro:bugdir alainhebert$ ./readme Darwin x86_64 GNU Fortran (GCC) 4.8.0 20120722 (experimental) Copyright (C) 2012 Free Software Foundation, Inc. GNU Fortran comes with NO WARRANTY, to the extent permitted by law. You may redistribute copies of GNU Fortran under the terms of the GNU General Public License. For more information about these matters, see the file named COPYING IPLIST= 504939689 IBASE(ILLIST)= 0 ***bug*** To execute, simply type ./readme